It's not a standard, but it's there: autocrypt (https://autocrypt.org https://autocrypt.org) aims to make end to end encryption as easy as possible. It's using

It's not a standard, but it's there: autocrypt (https://autocrypt.org https://autocrypt.org) aims to make end to end encryption as easy as possible. It's using PGP underneath but the whole idea is to hide key management (the real pain point) from the user. It's a long term initiative, divided in multiple levels of "compliance" that gradually break compatibility with existing systems more and more. Level 1 is there already, with some implementations.