I cited several words from my colleague Neruthes. He's not at LessWrong but he also joined the most recent Shanghai LessWrong meetup: https://www.lesswrong.com/events/zR4atrRmiaqGLvjYj/shanghai-lesswrong-meetup#NZHcXphJXcsTFwpmf
Recently we have been working on this project in the sense that I feel there is no good OpenPGP utility on Mobile (especially iOS). By good, I mean the UX should be good, and the license should be AGPL or GPL.
In the process, we got the idea of App Penetration — by making OpenPGP into keyboards (input methods), we can literally be end-to-end encrypted when using any channel of communication, as long as the other side can decrypt — on Facebook Messenger, on Telegram, on iMessage, whatever.
For now, we have been releasing Android beta test versions on Google Play. The iOS version on App Store. It might be a bit early to announce because there are plenty of bugs and a big shortage of tutorials, but I believe hardcore users can go through it.
There can be a lot of bugs and UX flaws. If you find any bug, just go to GitHub and open an issue. And I will appreciate!
In larger perspective, building Tessercube is just a humble beginning. We would like to give general public proper tools of encryption and make them possible to protect their privacy and enable the people to really own their data. That's why we also made Maskbook , an encryption and programmable layer on top of all existing giants, such as Facebook, Twitter, etc. I will write a separate post for our story and our approach.