At this point I would use Google Messages E2EE RCS over this since it usually doesn’t require convincing them to use it (if Android to Android)
If I was to convince them I wouldn’t target DekuSMS, instead I would target them to use Signal…
And you vet everything good with RCS instead of being stuck with SMS and MMS. Not to mention the fact that making it impossible to verify safety numbers (because “SMS”) over that is a huge downside.
Yes I like the concept but there’s far better solutions and if you’re gonna try to convince people to install an app, I would try Signal.