Synology Drive has all the features you want and with desktop (macOS, windows, Ubuntu) and mobile clients (iOS and Android). The potential downside is that you have to buy a Synology NAS to run it. I’ve had one for a number of years and I’m still very happy with it.

I also really like Resilio Sync. The downside there is that while the mobile client supports selective sync (you choose which files and folders to always have on-device) only the paid “pro” version of the desktop client supports it.

You make a very good point here. Currently the provided backup node is limited to 10GB, which is a lot, but probably not for what you are trying to accomplish. The Anytype folks have also stated that in the future they plan to charge for larger backup nodes, which may be something you want to avoid.

In the meantime, because syncing is p2p, I believe you can effectively self-host by just making sure you have an internet-connected machine always running the client app. In that way, there will always be a peer to sync to, even if your backup node is full and not accepting more data.

Not self-hosting, but I have been using Anytype for a few months now and absolutely love it. I’m doing a lot of online coursework, and so I’m using Anytype to take and organize my notes actively for several hours a day, every day. I also use it for task tracking, journalling, and it has just generally become the place where I dump any kind of info I might need to retrieve in the future.

There is a learning curve before you get the hang of it. I was also frustrated by the editor at first, but now that I have learned some of the slash commands, added in with markdown formatting, I find it to be really efficient. One oddity that likely trips folks up is that every paragraph is a separate “block” which makes partially selecting text across blocks impossible. On the other hand though, it makes grabbing a block and repositioning or reformatting the contents super simple.

Keep in mind that Anytype is offline first, p2p for syncing, and end-to-end encrypted. So the value of self hosting is, I suppose, not using their provided (currently free) backup node? It doesn’t seem like a big deal to me unless you don’t trust the encryption.