Whenever I question Signal on Reddit, I get downvoted to hell.
In terms of privacy, I still vastly trust Signal over WhatsApp, Snapchat, etc. But they've been sketching me out more and more lately. First was them making Signal dependent on Google services. Then there was them threatening to sue projects that attempted to create forks of the project without said Google dependencies. Now it's them not disclosing the source code for their server side software.
In their defense, the client is still mostly open source, but they need to stop acting like some savior for privacy when they are so hostile to open source.
I've had good luck with FitoTrack in F-droid. I was looking for a drop in replacement for the workout app on Apple Watch, and that seems to do well.