SumizAI vs MemexAI

What MemexAI is

MemexAI is an open-source (GPL-3.0) mobile app for iOS and Android, described by its developers as a "local, private AI journal." The name references the "memex" concept — a theoretical memory-storage-and-recall device described by Vannevar Bush back in the 1940s, long before personal computers existed. The app lets users capture life in three formats — text, photos, and voice — then uses artificial intelligence to automatically organize those entries into timeline cards and generate insights from them. The project was built in Hong Kong and puts particular emphasis on local-first processing, meaning minimal dependence on the cloud and external servers.

Key features

The ability to capture entries in three formats at once — text, photos, voice — sets MemexAI apart from typical text-only journals limited to writing alone. A voice recording of a brief reflection during a walk, a photo of an interesting spot, and a short text note can all land in the same journal entry, building a richer record of the day than text alone could capture. The AI layer automatically organizes these raw entries into timeline cards, saving the time of manually categorizing and tagging every entry individually. The insight-generation feature draws on patterns across entry history to, for example, flag recurring themes or moods — something hard to spot by manually scrolling through hundreds of past entries without an algorithm's help. The local-first approach means data stays mostly on the device, which matters for a category as personal as an intimate journal. The open GPL-3.0 source code lets users verify exactly how the app processes sensitive entries, instead of relying solely on privacy-policy claims.

Who it's for

MemexAI appeals to people keeping a personal journal who want to combine traditional writing with modern AI tools for automatically organizing memories, instead of manually sifting through stacks of old entries. It's a good choice for someone who started a paper journal or a simple note app but got discouraged from manually reviewing old entries in search of patterns and connections. It also suits privacy-conscious users who want AI support for reflection without sending every entry to a large advertising corporation's servers. The open source code additionally draws in technically minded users who want to understand how the app actually works before trusting it with their most personal writing.

Use cases

A typical scenario is an evening entry — a short voice recording summarizing the day, a photo of something interesting spotted on the way home, maybe a few lines of text summarizing emotions. After a few weeks of such entries, the AI might generate an insight like "you mentioned work stress more often this month than last" — information hard to notice without a systematic review of every entry. Someone working on mental well-being can use the timeline feature to track how mood shifted over weeks or months. A traveler can combine photos of places with short voice notes, building a multimedia trip journal without manually organizing files into separate folders.

Pricing and business model

MemexAI is entirely free and open source under the GPL-3.0 licence — no charge for downloading or for core journal and AI functionality. The community-driven development model means the project is sustained by developer contributions rather than subscription revenue, which is unusual for apps using AI features that typically incur compute costs covered by user fees or advertising.

Limitations and what to watch for

MemexAI is available only as a mobile app for iOS and Android — there's no desktop version, so reviewing and organizing a longer entry history on a bigger screen isn't possible without extra tools. Although the app markets itself as "local-first," AI-based features (insight generation, timeline organization) may in practice require processing data off the device, depending on whether the AI model runs locally on the phone or through an external API — worth verifying in the project's documentation before entrusting it with truly sensitive entries. As a smaller open-source project out of Hong Kong, MemexAI has no guarantee of long-term support or regular updates, unlike apps backed by large companies with a subscription model. The ai notes feature in MemexAI is limited to organizing and analyzing journal entries — there's no option for a free-flowing, substantive conversation with the model on any topic, unlike classic chatbots. Anyone looking for a journal with robust export options to other formats should check whether MemexAI offers a full way to take data out of the app before investing time building a long entry history.

What's worth checking before choosing

Before starting a journal in MemexAI, read the privacy policy and technical documentation carefully to understand exactly which AI features run locally on the device and which require a connection to an external server. Also check whether the app offers export of entries to a standard format (text or JSON, for instance) before building a multi-year history that would be hard to move elsewhere. If you're looking for ai notes focused on work and substantive conversations rather than a personal journal, MemexAI may not be the best match despite the similarity in feature naming.

Bottom line

MemexAI works well as a multimedia personal journal for someone who wants to combine text, photos, and voice in one place with AI help organizing memories. It isn't, however, a tool for ai notes in the sense of working, substantive records of conversations with a language model — for that, an app designed around conversation on any topic, rather than personal reflection and memory, will serve better.

Comparison with SumizAI

MemexAI and SumizAI both combine AI with saving personal content, but they differ in input format and purpose. MemexAI collects raw journal entries — text, photos, voice — and AI organizes them into a timeline with insights, creating something close to ai notes, but focused on personal reflection and memory rather than work or a substantive conversation with a model. SumizAI starts from a conversation with an AI model on any topic, and answers worth keeping land as Markdown files in a private vault — closer to working ai notes than an emotional journal kept in the evenings. Anyone looking for a tool to keep a multimedia journal with automatic pattern discovery will appreciate MemexAI; anyone who wants their ai notes to emerge from a substantive conversation with a language model and land in a searchable Markdown archive will find that in SumizAI.

What SumizAI is

A note-taking application built around a conversation with an AI model. You ask a question, the answer streams back, and the answers worth keeping become Markdown notes — filed into a vault that is a folder on your own disk.

A vault is a directory holding base.md, a generated table of contents up to six levels deep, and a notes/ folder with one .md file per note. Before a note is written it is checked against the ones already there, so the fourth note about the same idea gets merged instead of added. Links between notes are ordinary Markdown links to files that exist.

The model is never ours: you bring your own API key to one of seven providers — Anthropic, OpenAI, Gemini, Groq, OpenRouter, a local Ollama or your own server — and pay that provider directly. A question sends the table of contents plus at most five relevant notes within a 24,000-character budget, and the app shows you which five it used.

Every answer kept this way becomes one of these ai notes, ready to search again months later without hunting back through old chats.

Side by side

Where they differ

• Both mention AI. The difference is whose key it runs on: SumizAI never resells inference — you connect one of seven providers (Anthropic, OpenAI, Gemini, Groq, OpenRouter, a local Ollama or your own server) with your own API key and pay that provider directly. Check what MemexAI does with the model bill before comparing prices.
• MemexAI is open source (GPL-3.0), and SumizAI is not. If reading the source is what decides it for you, that is a real argument for MemexAI. The guarantee SumizAI offers instead is structural rather than legal: the notes are Markdown files in a folder you chose, so they open in any editor whether or not the application is running.
• AlternativeTo's description of MemexAI does not mention Markdown, so check what format your notes end up in before you fill it up. SumizAI writes standard .md files to a folder you picked, and an unpaid account can still export all of them.
• MemexAI's description mentions voice. SumizAI has no voice input and no transcription — the input is a typed conversation.

Which one to pick