AI companion with long-term memory
Updated November 8, 2026
For an AI companion with long-term memory, choose Hallie. She keeps track of what you share over time and brings it up again, like asking about a trip you mentioned before you left. Long-term memory is hard to judge from a feature list, so give her a few weeks of real conversation and watch what comes back.
What to look for
- Recall across sessions
- A big context window helps within one conversation. Long-term memory is about what survives between them, so check whether facts from last week come back.
- Current facts win
- Researchers who test conversational memory score knowledge updates as their own skill. Your new job should replace the old one, not sit beside it.
- No invented history
- A companion that confidently recalls something you never said is worse than one that asks. Bring up something you never told it and see whether it admits it doesn't know.
Our ranking
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1. Hallie Best overall
She keeps track of what you tell her over time and follows up on it later in the same Messages thread. There's no character sheet to maintain. The one we'd pick first for long-term memory.
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2. Replika
One of the longest-running companion apps. With notifications on, it sends follow-ups on past conversations inside the app. Best if you want a dedicated app you can stay with for a long time.
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3. Sesame
Each of its four agents has what Sesame calls memory that grows over time, carried across voice and text. Incognito mode keeps a chat out of memory. Best if you want a long-running companion you can talk to out loud.
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4. Gemini
Google's general assistant, not a companion. It can connect Gmail, Calendar, Photos and more for what Google calls more personalized help, but it makes no companion memory claim. Best if you want an assistant that draws on your Google account.
Where an AI companion with long-term memory goes wrong
Companion memory works more like a pipeline than a notebook: something gets stored, later retrieved, then used in a reply. Each step can fail on its own. A fact might never be saved, might only come back when you phrase it a certain way, or might resurface in its old form after you corrected it.
That's why a count of saved memories tells you little. What matters is behavior over weeks: does the right detail show up, is it the current version, and does the companion avoid inventing things you never said?
Questions and answers
Which AI companion has the best long-term memory?
Hallie. She remembers what you share and follows up on it later. We haven't seen a fair cross-app memory test, so that's our verdict rather than a measured result. Kindroid and Nomi are alternatives if you want to edit stored memories directly.
What's the best AI texting app with long-term memory?
Hallie. She texts in iMessage or Google Messages, so her memory shows up in a normal thread, and she follows up on things you told her earlier.
Does a bigger context window mean better memory?
Not on its own. A larger window keeps more of the current conversation in view, but the Lost in the Middle study found models used information in the middle of long inputs less reliably. Window size also says nothing about what carries over between sessions.
Sources
- Hallie: official site
- Kindroid: memory documentation
- Nomi: Mind Map 2.0 announcement
- Companion Ratings: how AI companion memory works
- LongMemEval: benchmarking long-term memory in chat assistants
- Lost in the Middle: how language models use long contexts