Encrypt and decrypt data between my app and website?

Hey all!  Is there an easy that anyone uses to encrypt and decrypt data through my app and my website? (PHP or ASP)

Basically, I want to setup some new game data for a multiplayer game, encrypt it and send it to my webserver, decrypt it, , modify it, save it, re-encrypt it and then be able to send it back to the other player.

Is there a best-practice that anyone uses to encrypt or otherwise obfuscate their data in this situation?

I’m new to this encryption aspect of Corona/lua coding so I’d love to hear what you all are doing!

Thanks!