Existential OCD: Why Philosophical Spirals Feel Impossible to Escape

Existential OCD involves intrusive, compulsive thoughts about unanswerable philosophical questions like reality, consciousness, and meaning that create distressing mental spirals, but evidence-based therapies like Exposure and Response Prevention (ERP) and Acceptance and Commitment Therapy (ACT) effectively treat this condition by teaching uncertainty tolerance rather than seeking philosophical resolution.

Have you ever felt trapped in endless loops of philosophical questions that demand immediate answers - questions about reality, consciousness, or free will that your brain treats like emergencies? You might be experiencing existential OCD, a recognized subtype that transforms normal curiosity into mental imprisonment.

What is existential OCD?

Existential OCD is a recognized subtype of OCD where intrusive thoughts fixate on unanswerable philosophical questions. These aren’t casual musings about the meaning of life. They’re relentless, distressing questions that hijack your attention: What if nothing is real? What if consciousness is an illusion? What happens after death? What if free will doesn’t exist?

Unlike healthy philosophical curiosity, existential OCD transforms these questions into urgent threats. A philosophy student might enjoy pondering the nature of reality during a late-night discussion. A person with existential OCD feels trapped in a mental loop, desperately searching for certainty about questions that have no definitive answers. The thoughts feel pressing, as if your brain won’t let you move forward until you solve the unsolvable.

This is a manifestation of obsessive-compulsive disorder, where the brain’s threat-detection system misfires. Instead of alerting you to real dangers, it treats philosophical uncertainty as an emergency requiring immediate resolution. You might spend hours mentally reviewing arguments, seeking reassurance from others, or researching online, trying to find the answer that will make the anxiety stop.

The condition is ego-dystonic, meaning you recognize these thoughts are irrational. You know that most people don’t obsess over whether they truly exist or whether reality is a simulation. You understand that endlessly analyzing these questions isn’t productive. Yet you can’t stop engaging with them. The thoughts feel different from your normal thinking, intrusive and unwanted, like a record skipping in your mind.

Existential OCD isn’t about being philosophical or intellectually curious. It’s about your brain treating uncertainty as a threat that must be neutralized immediately. The difference between wondering about life’s big questions and having existential OCD is the difference between enjoying a puzzle and feeling trapped in one you can never complete.

Common obsessions in existential OCD

Existential OCD doesn’t look the same for everyone. The philosophical questions that trap you might differ from those that trap someone else, but the underlying pattern remains the same: your mind latches onto unanswerable questions and refuses to let go. Recognizing your specific thought patterns can help you understand what you’re dealing with.

Reality and solipsism obsessions

“How do I know anything is real?” This question might hit you suddenly while you’re at work, talking to a friend, or lying in bed. You start analyzing whether the world around you actually exists or if it’s all a construction of your mind. The obsession deepens: “What if I’m the only conscious being and everyone else is just part of my imagination?” You might test this by looking for “proof” that other people have inner lives, scrutinizing their expressions for signs of genuine consciousness. No amount of evidence satisfies you because the question itself has no definitive answer.

Meaning and purpose obsessions

You find yourself stuck on the question: “What’s the point of anything?” This isn’t the occasional existential wondering most people experience. You can’t move forward with your day because you need to resolve whether life has inherent meaning before you can justify getting out of bed. The obsession forces you to analyze every action, every goal, every relationship through this lens until nothing feels worth doing.

Consciousness obsessions

“What is consciousness?” becomes an all-consuming question. You might spend hours trying to understand the nature of your own awareness, thinking, “How do I know I’m actually experiencing things?” You question whether your perceptions are real or whether you’re just responding mechanically to stimuli. Some people with these obsessions report feeling disconnected from their experiences, constantly analyzing whether they’re truly present in their own lives.

Free will obsessions

The question “Do I actually make choices or is everything predetermined?” can paralyze your decision-making entirely. You might stand in front of your closet, unable to choose what to wear because you’re analyzing whether the choice is truly yours or just the inevitable result of prior causes. “Am I really in control?” becomes a constant background hum that undermines your sense of agency.

Death and infinity obsessions

“What happens after death?” might seem like a universal human concern, but for someone with existential OCD, it becomes a relentless mental loop. You try to conceptualize eternal nothingness, asking yourself what it feels like. The impossibility of answering creates intense anxiety. Some people get stuck on infinity itself, trying to grasp the concept fully, knowing it’s impossible but unable to stop trying.

Identity obsessions

“Who am I really?” goes beyond normal self-reflection. You might obsess over what constitutes your core self, considering thought experiments like “Would I still be me if my memories changed?” These questions create a frightening sense of instability, as if your identity might dissolve if you can’t find satisfying answers.

Common compulsions and avoidance behaviors

People with existential OCD develop specific compulsive responses to manage their distress. These behaviors feel productive in the moment, like you’re working toward clarity or resolution. In reality, they trap you in a cycle that strengthens the obsessions and teaches your brain that these thoughts are dangerous enough to require constant management.

Mental rituals: the invisible compulsions

You might spend hours mentally replaying philosophical arguments, searching for logical proof that reality exists or that your consciousness is real. You review the same reasoning over and over, trying to reach a conclusion that feels satisfying or complete. Sometimes you mentally test yourself, asking “Do I feel real right now?” or “Does this moment feel authentic?” These mental rituals can happen anywhere, during conversations, while driving, or as you’re trying to fall asleep. They’re exhausting precisely because no one else can see them happening.

Reassurance seeking and research spirals

You might ask friends, family, or therapists variations of the same philosophical questions, hoping someone will finally say something that makes the anxiety disappear. Online forums become a minefield: you search for posts from others experiencing similar thoughts, reading hundreds of comments looking for the one answer that will click. Research compulsions can consume entire days as you read philosophy texts, neuroscience articles, or spiritual writings, convinced that the right information will provide certainty. You’re not reading out of genuine curiosity but out of desperation for relief. The temporary calm you feel when you find a compelling argument never lasts, which is why you keep searching.

Avoidance patterns that shrink your world

You might skip philosophy classes, avoid certain books or movies, or steer clear of conversations about meaning and purpose. Some people avoid meditation or mindfulness practices because focusing on awareness triggers obsessions about consciousness. Others avoid substances like alcohol or cannabis, fearing they’ll trigger derealization or existential panic. These OCD compulsions and avoidance behaviors might bring short-term relief, but they reinforce the false message that these thoughts and situations are genuinely threatening. Your world gradually becomes smaller as you navigate around potential triggers.

Anatomy of a spiral: a minute-by-minute breakdown

Understanding how these spirals unfold helps explain why they feel so impossible to escape. The progression follows a predictable pattern, even though each episode feels uniquely overwhelming in the moment.

Minute 0–1: The trigger arrives

You’re doing something ordinary, making coffee, scrolling your phone, sitting in a meeting. Then it hits: a word, a fleeting thought, a moment of awareness about your own consciousness. The intrusive thought arrives with sudden, electric urgency. “What if nothing is real?” “How do I know I exist?” The question doesn’t feel like a curiosity. It feels like an emergency that demands immediate resolution.

Minute 1–3: The failed dismissal

Your brain registers this as a threat, and anxiety spikes instantly. You try to brush it off. “This is silly, I’m fine, everyone has weird thoughts.” But the attempt to dismiss it backfires completely. The thought becomes more salient, more insistent. Your heart rate picks up. The question loops again, louder this time.

Minute 3–10: Engagement begins

You decide you’ll think it through just once to settle it. You’ll find the logical answer that puts this to rest. But each answer you generate spawns three new questions. “Okay, I exist because I think, but what is thinking really?” “If my brain creates my reality, how do I know my brain is real?” The philosophical spiral tightens. You’re no longer trying to dismiss the thought. You’re trying to solve it.

Minute 10–30: Physiological takeover

Your chest tightens. The world starts feeling flat or distant, like you’re watching life through a screen. Derealization sets in, which only confirms the fear that reality might not be solid. Panic builds. You’re desperately searching for the one perfect thought, the right angle of logic that will make the anxiety collapse. Someone asks you a question and their voice sounds far away.

30+ minutes: Full spiral engagement

Time distorts. You cannot redirect your attention no matter how hard you try. The outside world fades. You’re exhausted but can’t stop. The compulsion to resolve the question has completely taken over. There’s no satisfying conclusion, just mounting fatigue.

The false relief cycle

Occasionally, you land on something that feels right. A wave of relief washes over you. “Okay, I figured it out. I’m real because…” But within seconds or minutes, doubt creeps back in. “Wait, but what if…” The relief evaporates, and the anxiety returns even stronger than before. This cycle of temporary certainty followed by renewed doubt can repeat dozens of times in a single spiral, each false resolution making the trap feel more inescapable.

Why people get trapped in philosophical spirals

The trap of existential OCD isn’t about lacking intelligence or philosophical sophistication. It’s about a fundamental mismatch between how your brain processes threat and the nature of the questions you’re asking. When you have OCD, your mind treats uncertainty like a smoke alarm treats smoke: as an urgent signal that demands immediate action. But existential questions don’t just lack clear answers. They are inherently unanswerable by their very nature.

This creates a perfect storm. Your brain screams for resolution while confronting questions that have puzzled philosophers for millennia.

Your brain’s mismatch with unanswerable questions

People with OCD experience uncertainty as physical danger. When you wonder if you locked the door, checking provides temporary relief. But when you wonder whether free will exists or if reality is fundamentally real, there’s nothing to check. No amount of analysis can definitively prove you’re not in a simulation or that your choices truly matter.

Your brain interprets this lack of resolution as evidence that you haven’t thought hard enough yet. It’s like trying to fill a bucket with no bottom. The discomfort you feel isn’t philosophical curiosity. It’s your nervous system responding to perceived threat, demanding you find certainty where none exists.

The questions themselves are legitimate. Philosophers have debated consciousness, meaning, and reality for centuries. This legitimacy makes the trap especially insidious because you can always justify one more round of analysis.

Why thinking harder makes everything worse

The thing you’re doing to solve the problem is actually maintaining it. When anxiety spikes around an existential question, your instinct is to think your way out. You analyze, research, construct arguments, seek that one insight that will finally bring peace.

But this thinking is a compulsion. Just like hand-washing temporarily reduces contamination anxiety, philosophical analysis briefly reduces existential anxiety. The relief reinforces the behavior, teaching your brain that thinking is the solution.

Except it isn’t. Each answer generates three new questions. You might temporarily resolve whether consciousness is real, only to immediately wonder what “real” even means. The mind seeks a philosophical floor to stand on, but existential questions exist in infinite regress.

The intermittent reinforcement trap

Occasionally, you do experience moments of clarity. A particular line of reasoning clicks into place, and for an hour or a day, you feel settled. These moments are powerful reinforcers.

Intermittent reinforcement is one of the strongest learning mechanisms in psychology. When a behavior sometimes produces the desired result, you’ll persist far longer than if it never worked. Slot machines operate on this principle. So does existential rumination.

Those brief moments of resolution keep you coming back, convinced that if you just think about it the right way, you’ll recapture that sense of certainty permanently. But the relief always fades, often replaced by a metacognitive spiral: now you’re thinking about why you were thinking about the original question, analyzing your analysis, trapped in recursive loops that feel increasingly divorced from reality.

The philosopher’s trap: why analytical minds are vulnerable

If you’ve always been the person others turn to for thoughtful analysis, the one who loves a good debate or can untangle complex problems, you might find existential OCD particularly cruel. The very traits that make you intellectually capable become the tools of your own mental imprisonment.

People with strong metacognitive abilities can observe their own thinking with unusual clarity. You can track your thoughts about your thoughts about your thoughts, creating recursive loops that spiral deeper with each layer. While this capacity serves you well in academic work or professional problem-solving, it becomes a trap when applied to unanswerable existential questions.

The analytical approach that’s solved countless problems in your life now betrays you. Your history of thinking your way through challenges has trained your brain to believe that sufficient analysis will yield answers. When you hit a question with no provable solution, your mind simply tries harder, convinced that the breakthrough is just one more thought away.

If you have philosophical training or a deep interest in abstract thinking, you possess an even more sophisticated toolkit for obsession. You know the formal arguments, the counterarguments, the edge cases. You can construct elaborate thought experiments that make the uncertainty feel more urgent and real. Where someone without this background might have a fleeting worry about free will, you can build a comprehensive philosophical case that keeps you trapped for hours.

Your intelligence isn’t protecting you from existential OCD. It’s feeding it. The same mind that can grasp complex ideas and pursue questions with rigor is now using those abilities to strengthen the obsessive cycle.

Philosophy vs. compulsion: how to tell the difference

Many people with existential OCD worry they’re just overthinking, or that their distress is a normal part of philosophical inquiry. The truth is, healthy curiosity about existence looks and feels fundamentally different from the compulsive nature of OCD. Understanding these distinctions can help you recognize when philosophical thinking has crossed into something more concerning.

Time and natural endpoints

Healthy philosophical exploration has natural stopping points. You might spend an evening reading about free will, feel satisfied with new perspectives, and move on to other activities. With existential OCD, the thinking continues for hours without resolution. The questions don’t reach conclusions because the goal isn’t understanding; it’s eliminating anxiety.

Emotional quality

Pay attention to how the thinking feels. Genuine philosophical inquiry carries a sense of curiosity or intellectual enjoyment, even when grappling with challenging concepts. Existential OCD, by contrast, is driven by dread and a desperate need for certainty. The thinking feels urgent, distressing, and inescapable. You’re not exploring ideas because they interest you. You’re trying to solve them because the uncertainty feels unbearable.

Ability to disengage

Can you put the question down and return to daily life? Someone engaged in healthy philosophy can set aside metaphysical questions to focus on work, conversations, or hobbies. With existential OCD, the thoughts follow you involuntarily. This involuntary, intrusive quality is difficult to distinguish from normal philosophical inquiry at first, but it’s a critical marker.

Functional impact

Ask yourself whether engaging with these questions enriches your life or impairs it. Philosophy should expand your perspective, deepen your thinking, or connect you with others. If your existential questions are damaging your relationships, preventing you from working, or eroding your wellbeing, that’s a sign something has shifted from healthy inquiry to compulsion.

Ego-syntonic vs. ego-dystonic

Healthy philosophical thinking feels like you exploring ideas. The thoughts align with your interests and values. Existential OCD thoughts feel ego-dystonic, meaning they feel like something happening to you rather than thoughts you’re choosing to have. You might think, “Why can’t I stop thinking about this?” That sense of the thoughts being unwanted or alien is a hallmark of OCD.

Certainty-seeking vs. exploration

Genuine philosophical exploration embraces uncertainty as part of the process. You’re comfortable sitting with ambiguity and considering multiple viewpoints. Existential OCD is driven by certainty-seeking. You’re looking for a final answer that will stop the anxiety, a definitive proof that will let you relax. The goal isn’t learning; it’s relief. When you can’t find that certainty, the anxiety intensifies, driving more compulsive thinking.

Repetition and cycling

Healthy inquiry moves forward. You encounter new ideas, refine your thinking, and develop evolving perspectives. Existential OCD involves the same questions cycling endlessly. You’ve asked “What if nothing is real?” hundreds of times, examined it from every angle, and still can’t let it go. The repetition doesn’t bring new insight. It brings temporary relief that quickly fades, restarting the cycle.

Treatment for existential OCD

Existential OCD responds to the same evidence-based treatments that work for other OCD subtypes. The challenge is that these treatments require you to do the very thing your brain insists is dangerous: stop seeking certainty. Recovery doesn’t mean finding satisfying answers to life’s biggest questions. It means learning to live a meaningful life even when those answers remain forever out of reach.

Exposure and Response Prevention for existential themes

Exposure and Response Prevention (ERP) is the gold standard treatment for OCD, and it works for existential themes just as effectively as it does for contamination or harm fears. The principle is straightforward: you deliberately expose yourself to the uncertainty that triggers your anxiety, then resist the urge to perform compulsions that temporarily reduce it.

For existential OCD, exposures look different than they do for other subtypes. You might read a passage about the meaninglessness of existence and sit with the discomfort without mentally analyzing it. You might practice saying “I don’t know” when your mind demands an answer about free will. You might set a timer and allow yourself to feel the anxiety of uncertainty without researching, ruminating, or seeking reassurance.

The response prevention part is crucial. Every time you catch yourself spiraling into mental debate, you gently redirect your attention without engaging. You don’t try to solve the question or convince yourself it doesn’t matter. You simply notice the urge to figure it out and choose not to follow it. Over time, your brain learns that uncertainty isn’t dangerous, and the compulsive need to resolve these questions loses its grip.

How ACT helps you live with unanswerable questions

Acceptance and Commitment Therapy (ACT) is particularly well-suited to existential OCD because it doesn’t try to eliminate uncomfortable thoughts or provide reassuring answers. Instead, it teaches you to change your relationship with those thoughts so they no longer control your behavior.

ACT uses several techniques that directly address the existential OCD trap. Cognitive defusion helps you see thoughts as mental events rather than facts that require resolution. When your mind says “But what if nothing matters?”, you learn to observe that as a thought your brain is producing, not a problem you need to solve. Mindfulness-based approaches help you stay grounded in the present moment rather than lost in abstract spirals about reality.

The values-based action component of ACT is especially powerful. Instead of waiting until you’ve resolved every philosophical question, you identify what matters to you and take action aligned with those values. You might not know if free will exists, but you can still choose to call a friend. You might not understand the nature of consciousness, but you can still pursue work that feels meaningful. This approach helps you build a rich life even while carrying uncertainty.

If you’re ready to explore therapy options, you can start with a free assessment to connect with licensed therapists experienced in OCD treatment at your own pace.

Why traditional talk therapy can make things worse

Traditional talk therapy can actually reinforce the problem. When a therapist encourages you to explore and discuss your existential concerns in depth, it can become another form of compulsion.

Think about what happens in a typical therapy session focused on your philosophical worries. You articulate your concerns about meaning or reality. Your therapist asks thoughtful questions. You analyze your thoughts together, searching for insights or resolution. This feels productive, but it’s actually feeding the OCD cycle. You’re still trying to think your way to certainty, just with professional support.

Because existential questions don’t have definitive answers, this analytical approach never provides lasting relief. You might leave a session feeling temporarily satisfied, but within hours or days, your mind finds a new angle or a flaw in your reasoning, and you’re back where you started.

This doesn’t mean all talk therapy is harmful. A therapist trained in OCD treatment understands the difference between therapeutic processing and compulsive analysis. They’ll gently redirect you when you’re seeking reassurance and help you build tolerance for uncertainty rather than trying to eliminate it. The key is working with someone who recognizes existential rumination as a compulsion, not a philosophical inquiry that needs resolution.

Medication can also play a supporting role in treatment. SSRIs may help reduce the intensity of OCD symptoms, making it easier to engage with therapy techniques. They don’t answer existential questions or eliminate uncertainty, but they can turn down the volume on the anxiety enough that you can practice new ways of responding to intrusive thoughts.

The 3-minute spiral interrupt protocol

When you’re in the middle of an existential spiral, telling yourself to “just stop thinking about it” is like telling someone to win a staring contest by trying harder. The harder you push against the thoughts, the more they push back. This protocol gives you a concrete alternative: a sequence of steps that interrupts the compulsion cycle without requiring you to resolve the philosophical question or pretend it doesn’t bother you.

The entire process takes three minutes. You can do it anywhere, whether you’re at your desk, in a grocery store, or lying awake at 2 a.m.

Step 1: Name it (30 seconds)

Say to yourself, out loud if possible: “This is existential OCD, not a philosophical emergency I need to solve right now.” The phrasing matters. You’re not saying the question isn’t real or important. You’re recognizing that your brain is treating it like a crisis that requires immediate resolution.

If you can’t say it out loud, write it down or type it into your phone. The act of externalizing the thought helps create separation between you and the spiral.

Step 2: Anchor to physical sensation (60 seconds)

Place both feet flat on the floor. Press them down firmly enough that you feel the pressure. Notice the temperature of the ground through your shoes. Now place one hand on your chest or stomach and feel it rise and fall with your breath.

You’re not trying to calm down or make the existential dread go away. You’re simply redirecting your attention to something concrete and present. The philosophical spiral lives entirely in abstract mental space. Physical sensation pulls you into a different channel.

Step 3: Expand attention outward (60 seconds)

Name five things you can see right now. Don’t just glance at them. Actually look. Notice the color of the wall, the texture of fabric, the way light hits a surface. Then name three sounds you can hear, even if it’s just the hum of a refrigerator or distant traffic.

You’re deliberately shifting from internal focus to external awareness. The spiral wants all your attention pointed inward, analyzing and re-analyzing. This step practices pointing your attention somewhere else without fighting the thoughts.

Step 4: Commit to one values-based action (30 seconds)

Choose one small action you’ll do in the next five minutes that reflects what matters to you. Text a friend. Make coffee. Open the document you’ve been avoiding. Water a plant. The action doesn’t need to be profound. It just needs to be something other than ruminating.

This step transforms the protocol from a distraction technique into an OCD intervention. You’re practicing the core skill of acting according to your values even when your mind is raising urgent existential questions.

Why this protocol works

The spiral interrupt protocol targets the compulsion cycle at its weakest point: the moment between having the intrusive thought and engaging in the mental ritual. Most people with existential OCD don’t realize they have a choice in that moment. The thought appears, and they automatically start analyzing, seeking certainty, or trying to logic their way to peace.

This protocol inserts a different option. You’re not suppressing the thought or telling yourself it’s irrational. You’re acknowledging it exists and then choosing not to feed it with compulsive analysis. Each time you complete the protocol, you’re training your brain that existential uncertainty doesn’t require an immediate philosophical response.

What to say to yourself during a spiral

Having specific phrases ready makes the protocol easier to execute when your brain is foggy with anxiety. Here are some scripts you can adapt:

• “I’m noticing my mind is pulling me into an existential question. I don’t need to solve this right now.”
• “This feels urgent, but it’s not an emergency. I can let this question exist without answering it.”
• “My brain is doing the OCD thing where it demands certainty about something uncertain. That’s okay. I don’t have to participate.”
• “I might never know the answer to this question, and I can still make coffee and text my friend.”

Notice what these scripts don’t do: they don’t try to convince you the question doesn’t matter, they don’t offer reassurance, and they don’t attempt to solve the philosophical problem. They acknowledge uncertainty and redirect toward action.

When to seek professional help

Knowing when existential OCD has crossed from manageable to something that requires professional support isn’t always obvious. The philosophical questions feel important, even meaningful, which can make it hard to recognize when they’ve become harmful.

If your existential spirals are interfering with work, relationships, or basic self-care, that’s a clear sign. Perhaps you’re withdrawing from friends because social interactions trigger thoughts about the authenticity of connection, or missing deadlines because you’re mentally paralyzed by questions about free will. When the obsessions start dictating what you can and cannot do in daily life, professional help becomes essential.

Time is another useful measure. If you’re spending multiple hours each day engaged in philosophical rumination or mental compulsions, that level of preoccupation warrants clinical attention. Pay attention to distress intensity, too. If the emotional pain feels unbearable, if you’re experiencing physical symptoms like insomnia or appetite changes, or if you’ve tried self-help approaches without relief, these are indicators that you need more support.

When looking for a therapist, seek someone who specializes in OCD and has specific training in ERP or ACT. Ask whether they’re familiar with existential OCD as a subtype. Not all therapists understand that philosophical discussions can function as reassurance-seeking, so finding someone who gets the nuances matters.

If you’re unsure where to start, ReachLink’s free assessment can help you understand your symptoms and connect with a licensed therapist who specializes in OCD, with no commitment and at your own pace.

Learning to live with the questions

Recovery from existential OCD doesn’t mean you’ll finally discover the ultimate answer to life’s big questions. It means those questions will stop controlling your days. You’ll notice the shift when you can think about existence or meaning without immediately spiraling into hours of mental analysis. The uncertainty that once felt unbearable becomes something you can sit with, even if it never feels entirely comfortable.

Many people with existential OCD find that their relationship with philosophical questions actually deepens over time. The difference is choice. Instead of being dragged into existential spirals against your will, you can engage with these themes when and how you want to. Philosophy becomes voluntary again. You might read about consciousness or mortality because you find it genuinely interesting, not because your brain is demanding reassurance.

The questions don’t disappear, and you don’t stop being someone who thinks deeply about existence. But the distress fades. Those existential themes that once trapped you can eventually become a source of richness in your life rather than a source of suffering.

Finding support for existential OCD

The philosophical questions that trap you don’t need final answers before you can start living differently. Recovery means building a life where uncertainty exists but no longer dictates your choices. You learn to notice when your mind demands resolution and practice responding with action instead of analysis. The questions remain, but they lose their power to pull you away from what matters.

Working with a therapist trained in OCD treatment makes this shift possible. They understand that discussing existential concerns can become another compulsion, and they’ll guide you toward tolerance rather than resolution. ReachLink’s free assessment can help you understand your symptoms and connect with a licensed therapist who specializes in OCD, with no commitment and at your own pace. For support wherever you are, download the ReachLink app on iOS or Android.