I'm writing an application which recovers statistical data about a user. I'm still pondering about what would be the best way to encrypt the data. I haven't got any experience with mobile applications. But I was thinking of hardcoding an RSA public key and encrypting it in that way before sending it over the net.
Another guy working on the project suggested AES and hardcoding the pass phrase, but that seems to be a bad approach to me as a hardcoded password might be found through decompilation of the program. (I doubt someone would do it but just in case).
Are there any other approaches which would be better suited (setting up a ssl connection is not an option unfortunately) ?
I'm also still thinking about how I could provide integrity, I was thinking of hashing the file and then zip the whole package of message + hash into one file before encrypting it. If you have a better solution please feel free to share.