The topic I tested every open-source notes app on mobile — and only one actually competes with… is currently the subject of lively discussion — readers and analysts are keeping a close eye on developments.
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Going through note-taking apps is almost a hobby for me at this point. After Notion stopped being my go-to, the open-source world is where I naturally ended up. Most of them ship with at least one feature that’s pretty unique and they almost always cover the same ground of future-proof and local notes. AFFiNE, Joplin, Logseq, and Simplenote have all rotated in and out of my desktop setup over the past year, and they’re all pretty great.
But my desktop isn’t where most of my digital life happens, actually, my phone is. So if a note app doesn’t work on a phone, it’s not really my note app, it’s just my desktop note app. So I spent some time bouncing between the mobile versions of all four. Some of them disappointed me, to be honest, while others held up better than I expected.
AFFiNE is sort of the Notion-meets-Miro of the open-source world. It’s a workspace that combines docs, whiteboards, and databases into one local-first tool, and it’s the most ambitious of the four by a wide margin. I don’t need an account to use it locally on my phone, but I would need one to sync across devices through AFFiNE Cloud or to use any of the AI features. One thing worth flagging: the editor is mostly under MIT and AGPL, but the server-side sync portion runs on a separate non-FOSS enterprise license. So when people call it fully open source they’re glossing over that part.
The mobile version was genuinely enjoyable to spend time in. My favorite part is the Docs layout, with clean card previews showing timestamps and tags right on the home screen. Tagging is easy too and I like the color-coded dots and a clean inline modal for assigning them to a doc. The calendar journal works exactly like the desktop version where today’s entry auto-creates and I can scroll back through dates whenever I need to.
My one real issue is the Edgeless canvas. It’s basically view-only on mobile out of the box. I can pan around an existing whiteboard but I can’t actually edit shapes or build anything new from my phone. You can enable it under the Experimental Feature setting, but even then it’s pretty awkward to use; the tools are scroll-through at the bottom instead of fixed in place.
Joplin has been around forever and it runs on basically every platform you can name. The mobile app uses the same notebook-and-notes hierarchy as desktop, which I really love because the mental model carries over without any friction. No account needed either and everything stays local by default. If I want to sync I can plug into Joplin Cloud (which is paid), Dropbox, OneDrive, Nextcloud, or WebDAV. But I choose to keep the mobile and desktop versions separate.
What I love about Joplin’s mobile experience is the simplicity. Notebooks hold notes, and that’s pretty much the entire structure, so I’m not navigating a bunch of blocks, folders, or graphs. The WYSIWYG editor on mobile is also surprisingly capable. It fits into the cramped phone space without feeling watered down, and markdown is right there if I want to drop into it instead. Tags work really well too, and the configuration menu is properly deep with sections for plugins, markdown, note history, and import/export.
My one critique is that everything lives in an SQLite database. With Obsidian my notes are plain markdown files sitting in a folder I can open with anything. Joplin doesn’t give me that and I’d always wished it did.
Logseq is the block-based outliner of the four. Every line in a page is a bullet that’s also a block, and you build out pages by nesting them and linking with double brackets or hashtags. It’s local-first with no account required, and it stores notes as actual markdown files on disk. On my iPhone it auto-creates a folder I can browse in the Files app, and Android works the same way. Heads up for Android users though: Logseq isn’t on the Google Play Store, so you’d need to grab it from F-Droid or sideload the APK from GitHub.
I’ll be honest, the block-based editor works on desktop but I don’t think it translates to a phone. The touch targets are too small for thumbs, and the bottom toolbar of formatting and navigation buttons is really built for keyboard-first workflows.
I’d actually use the mobile app is for Whiteboards. That canvas drawing space is surprisingly capable on a phone, and I can even embed an MD block to put markdown content right into it. The bidirectional linking is the real Logseq pitch. Every tag and reference creates its own page automatically, I just don’t see myself doing that level of knowledge graph work on a phone.
Simplenote is made by Automattic, the same company behind WordPress, and it’s the only one in this group that requires an account because sync is basically the whole product. The client apps across iOS, Android, macOS, and desktop are all open source but the server is proprietary. So if a fully self-hostable stack is what you’re after, this isn’t it. Worth noting too: Simplenote hasn’t had any major new features since 2024 from what I can tell, so it’s more in maintenance mode than active development right now.
I had a clear favorite as soon as I opened it. My notes from desktop were instantly synced without any setup. The navigation is honestly like if Google Keep and Apple Notes had a baby and made it open source. A flat list of notes on one side and a clean editor on the other, and that’s basically the whole app. Tags live inline at the bottom of each note. Markdown rendering is built in too, so I can toggle between edit and preview, and the styled view actually looks decent.
I can’t really think of critiques for this one. The account requirement will probably bother some open-source purists. But for actually getting notes done on my phone, I think it’s the one of the four I’d reach for every day the most.
None of these are actually direct Notion replacements. AFFiNE comes closest but its database support is rough on mobile, but that isn’t really the point though. The point is having a go-to notes app the way Notion is the go-to for so many people. For me that’s Simplenote, just because it’s the easiest and fastest, and Joplin is pretty much tied with it. AFFiNE is decent on a phone but I prefer it on desktop. And honestly I think Logseq just doesn’t translate well on mobile.