“When you use Signal, your data is stored in encrypted form on your devices. The only information that is stored on the Signal servers for each account is the phone number you registered with, the date and time you joined the service, and the date you last logged on.”
While they do push the Play Store version, they also have an APK, and my understanding is that it does not rely on Google Play Services, though it might be buggier without them. If I recall correctly, the origin of Signal not being on F-Droid was related to the building and signature model that F-Droid used (builds by F-Droid, then signed by F-Droid’s keys), as mentioned in, eg, this issue. With that said, it has been pointed out that there are alternatives, like a separate repository, than, eg, the Guardian Project uses, and F-Droid apparently does now have a process for developer-signed apks.
Their general hostility toward outside developers and forks, however, and that the awkward server side code availability seemed to be related to the brazenly problematic cryptocoin advertisement, are extremely disappointing, however.
i forgot about this too. This is extremely disappointing.
Just to confirm what you said, I used Signal on LineageOS for over 6 months with no Google Play Services (installed through Aurora Store) – definitely doesn’t rely on them.