Syncthing Android App Discontinued

Looking at the underlying thread[1], the author mentions that it's very hard to publish on Google Play

> Reason is a combination of Google making Play publishing something between hard and impossible

Can someone expand on what's going on here?

[1]: https://forum.syncthing.net/t/discontinuing-syncthing-androi...

In this case the author doesn't want to use Storage Access Framework APIs to access the file system which were mandated a few years ago as the way to access data outside the app sandbox.

They're Java-only APIs and since Syncthings core isn't written in Java, the author would have to write JNI glue to call Android when writing/reading files (and honestly this would be quite tedious, because the way SAF works is to assign Uris to each file and you need to keep querying it to get folder structure since you can't just concat paths like with files).

The author didn't want to do that and tried to persuade Google to continue letting them access all files, all photos and all documents directly and Google said no. That was the "difficulty" - turns out it's really hard to publish on Play if you refuse to follow the guidelines. Just like on AppStore.

Many folks keep thinking that just because Android uses the Linux kernel, it is supposed to behave like GNU/Linux.

Likewise they will be rather surprised to insist in targeting iOS/iPadOS/watchOS as if they are UNIX clones.

Android being linux has exactly nothing to do with the fact that apps can't access resources outside their sandbox if they aren't mapped in somehow. Just like with lxc or docker containers on linux, jails on *bsd, or any other sandboxes.

The only Linux thing on Android is the kernel, use anything else at your peril regarding portability between updates and OEM custom forks.

https://developer.android.com/ndk/guides/stable_apis

The only linux thing is always the kernel. Userspace isn't linux by definition on any* system. That might seem like a pedantic point to make, but I would like to point out that gnu utils aren't required to make a system "Linux", and whether you're using a drop-in replacement like uutils or go a more different route doesn't make it any less "Linux".

Android Apps are and mostly always have been restricted to the Java virtual machine (or its modern equivalent) exactly because that makes them portable between sometimes quite different base systems from different vendors. If you insist that makes it less of a Linux system I'd like to know what you think of flatpak apps on top of immutable distros. I hope you agree that, conceptually, they're quite close actually.