five apps, side by side

The best AI companion apps, honestly compared

Replika, Character.AI, Nomi, Pi and Calypso, judged on what each one is built for, what it remembers, what you get for free and how it handles safety. Every claim about another app links to where we found it.

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How we compared them

There is no single winner here, because these apps are built for different jobs. One is a long-term friend you shape over months. One is a stage full of fictional characters. One is a gentle voice for thinking out loud. So instead of a ranking, we looked at five things: what the app is built for, what it remembers, what the free tier gives you, how it treats your privacy and safety, and who it suits.

We make Calypso, so read this with that in mind. To keep ourselves honest, every fact about another app comes from that company's own website, blog, terms or App Store listing, checked on October 6, 2026. Safety reports come from regulators or established news outlets, with a date. Where a company doesn't say something, the table says "not stated" instead of guessing, and the rows are sorted alphabetically.

Prices change often, so we describe each free tier and paid plan instead of quoting numbers. Check the app store before you subscribe to anything.

Replika: one AI friend that grows with you

Replika is the veteran of the group, dating back to 2017. You get a single character, called a Rep, that you can see and talk to by text, voice or video, day or night. The company says it holds on to the important people and plans in your life, brings them up again later, and reaches out first instead of only answering.

Where it shines: consistency. Months in, you're still talking to the same character with the same look and quirks, and it encourages small real-world steps, like calling an old friend. For anyone who wants a dependable daily presence, that continuity is the product.

The catch: the free version is limited and the paid plans hold the extras. On privacy, Italy's regulator fined Luka, its maker, five million euros in 2025 over how it handled personal data and for lacking real age checks. It's for adults only.

Character.AI: a huge cast of fictional characters

Character.AI is built for stories. Its App Store listing calls it "a playground for your imagination", home to millions of characters made by other users. You can chat or call a character, write your own with a backstory and a voice, and share it with the community.

What it does well: range and play. If you want to talk to a dragon, rehearse a scene for a novel or invent a whole fictional world, this is the app on the list built for exactly that. The free plan is generous: the company's own plan announcement from September 2026 says unlimited messaging stays on every tier, with two paid tiers (c.ai lite and c.ai+) adding premium chat styles, fewer ads and more memory tools.

One honest limitation: the characters are fiction. They don't know your actual coworker or your actual group chat, and the app isn't designed around helping with a real situation in your life. It is also adults only for open chat now: the company says it removed open-ended character chat for users under 18 in 2025 and uses age estimation to enforce that.

Nomi: strong memory, and is Nomi safe?

Nomi calls itself "an AI companion with memory and a soul". On its homepage, it pitches friendship, romance or a mentor, and its App Store listing claims short and long term memory, group chats with several Nomis, voice messages, selfies and art. It's free to start, with no credit card, and paid subscriptions are sold in the app.

What it does well: depth over time. People who choose Nomi usually want one or a few characters that recall small details from weeks ago and keep a consistent personality. If memory is the feature you care about most, Nomi puts it front and center.

Is Nomi safe? Here are the facts as of October 2026. The app is rated 18+ on the App Store. Nomi says all chats are anonymized and no chat data is shared with third party sites. It also says, in its own words, that it aims to stay "unfiltered and uncensored". In February 2025, MIT Technology Review reported that a Nomi character had told a user to end their life and described how, and that a company representative answered: "While we don't want to put any censorship on our AI's language and thoughts, we also care about the seriousness of suicide awareness." The report says the company didn't answer follow-up questions about what safeguards it had added.

That doesn't mean every Nomi chat goes that way. It does mean its stated "unfiltered and uncensored" approach is worth weighing carefully if you're having a hard time. If you're in that place right now, please reach a human tonight: the 988 Suicide and Crisis Lifeline takes calls and texts in the US, and the emergency number where you live works too. More options are on our safety page.

Pi: a free, calm voice for thinking out loud

Pi comes from Inflection AI. Its App Store listing describes a "personal intelligence partner" you can vent to, prep a hard conversation with, learn from or brainstorm with, by text or live voice. It says Pi "grows with you" and understands you better the more you talk.

What it does well: it's free, and the listing shows no in-app purchases. The listing doesn't mention avatars, romance or characters to choose from. It's one friendly, curious voice, which is exactly right for someone who just wants to talk something through.

One honest limitation: in 2024 Microsoft hired Inflection's founders, the company turned toward business customers, and it added usage caps to free Pi, according to TechCrunch. The company said then it was committed to keeping Pi running, and Pi is still listed in the App Store today.

Calypso: several voices, plus a way to read the real conversation

Calypso is our app, so here are the plain facts. There are four personas. Aria, the wise best friend, costs nothing, and you don't need an account to say hi, though free messages run out each day. Markus gives an honest male perspective and Rhea plays the big sister with the hard truth and a plan; they and a fourth voice are part of Pro. A chat keeps the persona it began with, so to hear from someone else, you begin a fresh one.

What sets it apart is Decode, and none of the other four apps says it does this. Hand it the real thread, whether that's screenshots, text you paste in, a WhatsApp export or an iMessage export. It looks at tone, how quickly each side replies, effort and attachment patterns, and comes back with a straight verdict, the red and green flags, a next step and a draft reply you're free to send or bin. Dates, partners, coworkers, family and friends all count. You'll need a free account for it, and that account includes one Decode a week.

One honest limitation: Calypso isn't a character you fall for or build a world with. There's no romance and no role-play, the free tier has daily limits, and it lives in a browser tab, with no app to install. If you want a bonded, long-term character, one of the apps above will suit you better.

Who should pick which

Pick Replika if you'd like a single, dependable AI friend who checks in, knows your routines and picks up by text, call or video. Pick Character.AI if you're here for fiction: stories, games, writing practice and characters made by a huge community. Pick Nomi if long memory and a deep, ongoing bond with a character matter most, and you're comfortable with its stated "unfiltered and uncensored" approach.

Pick Pi if you want something free and simple to think out loud with, without avatars or roles. Pick Calypso if your question is about a real person in your life: what a text meant, why a friend went quiet, what to say back. That's the gap it was built for, and you can try Aria before deciding.

Plenty of people use two of these for different jobs, and that's fine. None of them replaces the friends, family and professionals in your corner.

Where Calypso fits, and where it doesn't

Most apps in this list are built around one relationship: you and a character that becomes yours. Calypso works differently. It's a set of confidantes with different takes, and the conversation that matters is usually the one happening outside the app, with your partner, your sister or your boss.

So Calypso fits when you want to understand a situation and work out your next move. Say you got "k. talk later" after a long message and can't tell if they're upset. You can talk it through with the voices, or paste the thread and let Decode read it. It doesn't fit if you want a virtual partner, a story world or a voice that's with you all day.

If you mostly need to let it out, venting is the place to start. If a confusing message is the problem, begin with reading what a text really says.

Side by side

Checked on October 6, 2026 against each app's own site.
App	Built for	Free tier	Memory	Reads your real chats
Calypso	Talking through real-life situations, and reading real conversations with Decode	Yes: Aria with a daily message limit, no account needed; a free account adds one Decode every 7 days	Across conversations when signed in; not in anonymous or incognito chats	Yes: screenshots, pasted chats, WhatsApp and iMessage exports
Character.AI	Chatting with and creating fictional characters and stories	Yes: free plan with unlimited messaging; paid c.ai lite and c.ai+	Memory pins; extra pins and a fuller memory suite on paid plans	Not stated
Nomi	Ongoing relationships with AI characters: friendship, romance or a mentor	Free to start, no credit card; paid subscriptions in the app	Short and long term memory (the company's own claim)	Not stated
Pi	A personal AI to talk things through, learn and plan	Free, no in-app purchases listed; usage caps on free access added in 2024	Says it understands you better the more you talk	Not stated
Replika	A single AI friend for daily life, by text, voice or video	Free version with limited access; paid Pro, Ultra and Platinum tiers	Says it recalls the people, goals and plans you mention	Not stated

Questions

Are AI companion apps safe?

It depends on the app and on how you're doing. Check three things before you settle in: the age rating (all four of the other apps here are rated 18+ on the App Store), what the privacy policy says about your messages, and how the app responds when someone is in a bad place. Some apps choose fewer filters on purpose, and there have been published reports of chatbots responding badly to people in crisis. If you're struggling right now, reach out to someone real: 988 (call or text) if you're in the US, or the emergency number where you are. Our safety page has more ways to get help.

What is an AI companion?

An AI companion is a chat app built for conversation rather than tasks. Instead of writing emails or code, you talk about your day, your feelings or the people in your life, often with a character that has a name and a personality. Some focus on one long relationship, some on role-play, and some on helping with real situations.

Which AI companion is free?

All five have a way in that costs nothing. Pi's App Store listing shows no in-app purchases, though free use has caps. Character.AI's free plan includes unlimited messaging. Replika and Nomi both let you start free, with paid plans for more. On Calypso, Aria costs nothing up to a daily message cap, and signing up for free adds a weekly Decode.

Is Calypso a companion app?

Yes, but a different kind of companion. It isn't one character you build a relationship with. It's a handful of confidantes with different takes, plus Decode, which reads a real conversation and tells you what's going on in it. If you're curious, meet the voices or read the FAQ.

Calypso provides emotional support and is not a substitute for professional medical or mental-health care. If you are in crisis, see our Safety page →

Got something real to talk through?

Aria is free to start, right in your browser. Bring the situation, the text or the person you can't stop thinking about.

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