I like to use PGP whenever I can. Not everything I send is necessarily super sensitive or private, but I’d prefer it to never show up in a leaked database. Good thing Google has been working on a Chrome extension End-to-End to add PGP support to Gmail.
https://github.com/google/end-to-end
source – http://conorpp.com/blog/How-to-support-PGP-encryption-in-Gmail/
android app - https://play.google.com/store/apps/details?id=org.sufficientlysecure.keychain
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