Basically, what the title says. Do you use any app, that is proprietary, but either has no OSS alternatives or they’re all not good enough? If there is an alternative, what keeps you from switching?
MicroG works really well
A free-as-in-freedom re-implementation of Google’s proprietary Android user space apps and libraries.
MicroG works well if you let it leak some data to Google.
I would like a free-as-in-free-from-Google Google Play Services reimplementation that lets me use any app that depends on it without hitting any Google server.
OP asked about Open Source not about privacy.
MicroG minimises connections to google servers, here you can read what addresses it still connects to and why: https://github.com/microg/GmsCore/wiki/Google-Network-Connections
Free software (not open-source, it’s really free software that’s important) that depends on a single for-profit vendor is not free.
MicroG is open-source but it’s not free. It fails to address two problems:
- What do I care looking at the source code of a Google Play Services replacement when Google still holds my cellphone by the balls for certain critical functions?
- Why do I need permission from Google for apps to function properly on my cellphone?
I don’t think OP cares about getting the source of the apps they run so much as the apps being free-as-in-libre in his original question. Many people mistake open-source for free software and MicroG is not truly free.