I've come to realize that a lot of foss android apps are pretty outdated and usually abandoned. Is that even safe to use? Like even the fdroid archive repository, are those safe to use? I'm still rather new to the foss world, but in my mind it seems a very outdated app is probably not safe or am I missing something here?
I am not sure what you mean with the repo archive being outdated, the latest commit was 30 minutes ago. Could you please tell us more what apps you are referring to and in what way you find the repo archive being outdated? Might be easier to answer your question that way.
Also bear in mind that its quite common for stable releases to be some time apart from each other. Florisboard for example had its latest release over a year ago, but is being actively maintained.
save