Pi is a free chat assistant from Inflection AI built around conversation rather than getting things done. You open it to talk something through — a decision you're stuck on, a hard conversation you're about to have, a topic you want explained slowly, a language you want to practice out loud. It answers in a warm, unhurried voice (there are eight to choose from), asks follow-up questions instead of dumping a wall of text, and keeps a light set of reminders and lists. It's aimed at people who want a patient sounding board on their phone, not developers or researchers who need a workhorse. The catch: most of the team that made Pi feel special left for Microsoft in 2024, and the company now sells enterprise AI. What's left is still pleasant and still free — but it's coasting.
Key Features
- Conversation-first design — Pi is tuned to go back and forth. It asks clarifying questions, keeps replies short enough to actually respond to, and doesn't lecture, which makes it genuinely useful for thinking out loud or rehearsing what you want to say to someone.
- Free voice mode with eight synthetic voices — tap the headphones icon and you can talk hands-free while walking. The voices sound natural, with real inflection, though they carry a slight English accent and handle languages other than English less well.
- Completely free, no upsell — there's no Plus tier, no locked model, no message counter staring at you. Every feature sits on the free account. Heavy use can hit a soft rate limit, but there is nothing to buy.
- Reminders, lists and light memory — Pi can set reminders, keep to-do and shopping lists, and carry some context between chats. These agentic pieces arrived in 2025–2026 updates and are basic next to a dedicated task app.
- Runs anywhere without setup — start typing at pi.ai with no account, or install the iOS and Android apps to sync your history across devices.
Screenshots
Why You'll Love Pi
It talks like a person, not a search box
Most assistants treat every message as a transaction: you ask, they answer, done. Pi is built the other way. It slows down, checks what you actually mean, and reflects things back before offering an opinion. That rhythm is the whole point — it's why Pi works for venting before a difficult call, second-guessing a job offer, or being walked through a concept one step at a time. It's also a low-stakes partner for practicing a language, since it will keep a simple conversation going and correct you gently. None of this is groundbreaking anymore, but the tone still holds up.
Free with nothing dangled behind a paywall
ChatGPT, Claude and Gemini all reserve their best models, longest context and heaviest usage for paying subscribers. Pi doesn't do tiers. You get voice, memory, reminders and web-connected answers on a free account, and the only ceiling is an unpublished rate cap that most people won't reach in normal use. The honest reason it's free is less flattering: Inflection makes its money selling enterprise AI now, and the consumer app isn't a business it's trying to grow. You're using a well-made product that its owner has mostly stopped developing.
Where it falls short
Pi is not a workhorse. It won't write or run code well, it struggles with math and structured analysis, and third-party reviewers estimate its context window at roughly 8,000 tokens — Inflection doesn't publish a figure — which puts long documents out of reach. Memory is shallow next to what ChatGPT and Gemini now carry across sessions. The slowdown is real: the founders and most of the roughly 70-person team left for Microsoft in March 2024, Microsoft paid about $650 million to license the technology, and new CEO Sean White has pointed the company at enterprise deals and on-premises deployments. Pi now runs on an orchestration layer across several models rather than Inflection's own. There have been some updates since — better voice, the reminder tools, and a small consumer experiment called Pi Journeys launched in July 2026 through Inflection AI Labs — but the core assistant hasn't kept pace with the field. The messaging-app versions on WhatsApp, SMS, Messenger and Instagram were switched off in May 2024, so it's web and mobile apps only now. On the App Store the iOS app sits around 4.4 stars from roughly 2,400 US ratings; the Play listing shows more than a million installs, but third-party trackers put its Android rating closer to 3 stars, which suggests Android users have had a rougher time.
Category: AI assistant
Platform: Web, iOS, Android
Price: Free, with no paid tier
Frequently Asked Questions
Yes, completely. There's no subscription, no Pro tier and no per-message charge; voice, memory, reminders and web search are all on the free account. Very heavy sessions can hit an unpublished rate limit that clears after a short wait. The real cost is that the app is in maintenance mode, not that it asks for money.
No. Pi needs an internet connection for everything. All the processing runs on Inflection's servers, there's no on-device mode, and chat, reminders and voice mode all stop working without a signal.
On iOS the app asks for microphone and speech-recognition access for voice mode, plus notifications for reminders. It collects your account details (name, email) and the text and voice you send, and by default that content can be used to train Inflection's models — you can turn that off in Account settings. It doesn't need contacts, location or camera access. You can also use pi.ai in a browser with no app and no account at all.