Pocketstar Signal - contains proprietairy libraries, namelely Google Maps integration, the rest of the code is FOSS.
Do these Google Maps integrations connect to Google servers if the user doesn't engage with the location feature, or does it depend on whether unprivileged Google Play Services are installed?
If the Google Maps integration in Signal are dormant without Google Play Services, then installing Signal might be preferable for those who aren't interested in Unified Push or the security features of Molly.