Currently the app doesn’t have a lot of the functionality I require like split tunneling but I have great respect for Lavabit seeing as they were one of/if not the first encrypted email service to arrive, utilised by Edward Snowden, and they decided to close shop rather than divulge keys to the gov when requested. Plus they are currently working on a new encrypted email protocol which I would like to utilise when available.
I won’t be using Proton as they seem to follow Apple’s premium pricing philosophy and require account creation. Mullvad is more respecting of privacy via not needing an account but the only anonymous way I see of paying for their service is by sending cash to them via post which isn’t very economical.
If you click the link I provided it takes you to the app on the google play store which also links to their website and is registered under Lavabit LLC. Additionally if you search for the app it is open source and attached to their GitHub account.