7 best private AI chat apps in 2026

A private AI chat app can mean a few different things. It might run the model on your phone, so nothing you type has to leave it. It might send your message to a server run by a company that promises not to log it. Or it might keep your chats encrypted on your device and still pass each prompt to a big AI provider. All three get called private, and they protect different things.

There’s a second question that gets less attention: what happens to a conversation once it’s over. Most of these apps keep a chat history you can scroll back through. A few go further and remember details from one conversation to use in the next. That’s useful, and it’s also the part you’ll want to be able to see and control.

This list is published by the team that builds Merrin, and Merrin is first on it. It’s labeled for what it’s good at, personal conversations and memory, and not as the best overall pick, because these seven apps do different jobs.

The 7 apps at a glance

How we compared them

We looked at five things for each app: where the AI runs, whether it works offline, whether it supports voice, whether it remembers anything between chats, and what it costs. Every detail about another company’s app comes from its own website, documentation, or store listing, last checked on October 30, 2026. We didn’t run speed or quality benchmarks, and we haven’t tested the other apps in airplane mode, so we only say an app works offline when its maker says so.

Where the table says “Not documented,” we couldn’t find the feature in the app’s own materials. That doesn’t prove the app lacks it.

1. Merrin: best for personal memory and journaling

Most offline AI apps are built to answer questions privately. Merrin is built for a different kind of conversation: the kind about your own life. You talk or type about what’s on your mind, and it asks follow-up questions. You can have it just listen, coach you toward a decision, or argue the other side. Over time it keeps a journal of those conversations and remembers what matters, so you can come back to them later. Our page on conversational journaling shows how that works.

It’s meant for people who want a private place to think out loud.

• The AI runs on your phone. Conversations, voice transcripts, journal entries, and memories are designed to stay on the device during normal use. There’s no account to create. Core features work without internet once the AI models are installed.
• You can talk instead of type. Voice conversations are on the free plan, and speech recognition is designed to run on the phone too.
• Its memory is yours to edit. Merrin remembers the people, plans, and decisions you mention. Every memory can be viewed, corrected, or deleted, which we explain in AI memory you can see and delete.
• It connects what you say today with what you said before. Search works by meaning, so “that job I wasn’t sure about” can find the right conversation even if you never used those words. On Pro, insights also show what keeps coming back and when your view on something changed.

One more limit to know about: if you dictate with your phone keyboard’s built-in microphone instead of Merrin’s own voice mode, that uses the operating system’s speech service, which isn’t guaranteed to stay on the device. The privacy policy lists everything Merrin does send over the internet: model downloads, purchases, configuration checks, and optional diagnostics.

Price and platforms: iOS and Android. The free plan has no message limits and includes text and voice conversations, automatic journal entries, memory, and search by meaning. Pro adds insights into what keeps coming back and how your views change, weekly reflections, the Analyst, Future You, and Devil’s Advocate perspectives, and a larger AI model, for $29.99 a year or $99.99 once.

Merrin vs. the other six

Running the AI locally doesn’t set Merrin apart on its own. Private Mind also runs offline and also transcribes speech on the device, and AnythingLLM’s Android app can keep documents and memory offline too. What’s different is what Merrin does with a conversation afterwards: it turns it into a journal entry, keeps the details that matter in an editable memory, and connects them to things you said weeks ago. If you mostly want answers to questions, a general offline app is a better fit.

The other six, reviewed

2. Private Mind: best for offline questions about your documents

Private Mind is a free, open-source app from Software Mansion, a company known for its work on React Native. It runs open models such as Llama, Gemma, and Qwen on your phone, and version 1.3.5 added Liquid AI’s LFM 3 models, including one that answers questions about your photos. You can import a PDF or text file and ask about it, and each answer links to the passage it came from, so you can check it. Speech-to-text runs on the device through Whisper, and a built-in benchmark shows how fast each model runs on your phone before you commit to it. Its App Store and Google Play listings both declare no data collected, though the Google Play listing also says it may share app activity with third parties, without saying why.

Price and platforms: free. iPhone and iPad with iOS 17 or later, Macs with Apple silicon through the App Store, and Android.

Choose it over Merrin when you want to ask questions about documents offline, or you’d like to pick and compare models yourself.

3. Private AI: best for local models on Android

Private AI, published on Google Play by FireEdge, is a plain offline chat app. It comes with a catalog of built-in models, with Gemma 2 as the default and options including Llama 3.2, Phi-3.5 mini, and Mistral, and you can switch between them. Conversations are searchable, there are no ads, and the listing’s data safety section says no data is collected. With the paid upgrade, you can load any compatible GGUF model file.

Price and platforms: free on Android. Google Play lists one in-app purchase, at $9.99.

Choose it over Merrin when you’re on Android and want a no-frills offline chat with a range of models to try.

4. Jan: best for desktop AI with model choice

Jan is an open-source desktop app, under the Apache 2.0 license, for running models on your own computer. It works fully offline with local models, can run a local API server so other apps on your computer can use the same model, and supports MCP connectors for tools. Its privacy page says there’s no data collection until you choose to allow anonymous usage counts.

Price and platforms: free. macOS, Windows, and Linux.

Choose it over Merrin when you work on a computer and want to try many models, or plug a local model into other tools.

5. AnythingLLM: best for document workspaces

AnythingLLM organizes your files into workspaces and lets you ask questions across them. The desktop app includes a built-in local model and a local speech-to-text option, and it can read replies aloud. Its memories feature is off by default. Once you switch it on, it picks up short facts about you from recent chats, and you can view, edit, or delete each one. There’s also a free, open-source Android app that works offline with an on-device model, documents and memory included; an iOS version is planned without a date.

Price and platforms: the desktop app is free; AnythingLLM says it will stay free for 99% of features. An optional Pro subscription removes daily limits on some extra AI tools. macOS, Windows, Linux, Docker, and Android.

Choose it over Merrin when your private material is mostly files: contracts, research, meeting notes, a folder of PDFs.

6. Proton Lumo: best for private cloud AI

Lumo is Proton’s AI assistant, from the company behind Proton Mail. It runs on Proton’s servers, and Proton says it keeps no logs of your chats and doesn’t train on them. Saved history is zero-access encrypted, meaning Proton can’t read it. Lumo has memory: switch it on, and Lumo learns your preferences and context, and you can view, edit, or delete what it keeps. Memory needs a Proton Account and works on free and paid plans. You can dictate messages on the web and in the mobile apps.

Price and platforms: free tier; Lumo Plus is $9.99 a month billed yearly ($119.88). Web, iOS, and Android.

Choose it over Merrin when you want a capable general-purpose assistant and are comfortable with a cloud service under a no-logs policy.

7. Duck.ai: best for anonymous cloud chat

Duck.ai is DuckDuckGo’s free chat service. It gives you a choice of models from several providers, including OpenAI and Anthropic, and passes your prompts on without your IP address. Recent chats are stored on your device, not on DuckDuckGo’s servers, unless you turn on its optional sync, which stores them encrypted so DuckDuckGo can’t read them. Voice chat streams your audio to OpenAI through an encrypted relay, and DuckDuckGo says neither company keeps the audio after the session.

Price and platforms: free; DuckDuckGo’s paid Plus and Pro plans add more advanced models and higher limits. Works on the web and in the DuckDuckGo browser on Mac, Windows, iPhone, iPad, and Android.

Choose it over Merrin when you want quick answers from familiar cloud models and the questions aren’t personal.

Our ChatGPT alternatives list goes deeper on the retention and training policies behind Lumo, Duck.ai, Jan, and AnythingLLM.

On-device or private cloud?

With a local app, your words stay on hardware you control, and the risks are the device itself and its backups. With a private cloud service, the server has to read your message to answer it, and you’re relying on the company’s promise about what happens next. Proton and DuckDuckGo have published specific promises, but you can’t check from your side whether they’re kept.

Cloud models are bigger, so they know more and can search the web. Local models are smaller, need storage, and run better on a recent device. Our on-device vs cloud AI comparison goes through the trade-offs one by one.

Which private AI chatbot is right for you?

Choose Merrin for private conversations, voice journaling, and a memory of your own life you can read and edit.

Choose Private Mind for offline questions about documents on your phone, with web search there if you switch it on.

Choose Private AI for a simple offline chat on Android with plenty of models to try.

Choose Jan if you’re on a computer and model choice matters most.

Choose AnythingLLM if your work centers on documents and you want them in organized workspaces.

Choose Proton Lumo or Duck.ai when a private cloud service suits you better than managing models on your own device.

These aren’t exclusive. You might keep a cloud assistant for research and code, and a local app for the things you’d rather not send anywhere. If you want that second one to remember what you’ve talked about, and keep a journal as you go, Merrin is free to download on iOS and Android.