Telegram, widely hated on HN, years ago I think published how to verify their builds. Yes, on iOS you'll need a jailbroken device to do it but it was doable.

Telegram, widely hated on HN, years ago I think published how to verify their builds. Yes, on iOS you'll need a jailbroken device to do it but it was doable. (Writing in past tense since I haven't checked lately.) Edit: unlike WhatsApp, Telegram never was caught pants down uploading unencrypted data to Google with a wink wink, nudge nudge agreement. And they never got caught uploading data to Facebook directly" from the endpoint "for security before sending it end-to-end encrypted between endpoints. Oh, and they never got caught sending unencrypted data over the https port. (When normally extremely pedantic HN-ers write that Telegram sends data unencrypted, it means it is not end-to-end encrypted, not that it is plain text. Again contrary to what WhatsApp was caught doing.) Disclaimer: I use Telegram myself, recommend Signal short term and I'm actively looking for a better solution for the future. Current bets: Matrix for group chats and I am also (probably too) excited about nostr for future social networking.