I'm developing a web app which emails encrypted data (from a web form) to a client who uses Macs/OSX exclusively in their office.
I'd like to know: Is there are any reliable solutions for PGP / GnuPG decryption on Mac OSX mail?
I've come across Symantec's solution, but haven't read a great deal of positive feedback on it.
What about GPGTools? Has anyone had experience with it? Does it work seamlessly with Mac Mail? I can't remember where I read it and can't find it now, but can GPGTools decrypted email be index/searched in Mail? How susceptible is it to being disabled on a Mac Mail or OSX update?
I am using PGP Desktop for Mac by Symantec and it works pretty well. The thing with Mail plugins is that Apple has not come around to stabilize the API. It is my understanding that Mac GPG has a Mail plugin but it needs to be updated (or Mail has to be convinced about its compatibility) every time a patch bumps up the version number of Mail. This is a non-issue if you want to use alternative mail readers like Thunderbird, of course.
What Symantec's solution does is it interferes with the SMTP/POP/IMAP connection and proxies it instead. Through that proxy the connection between Mail and your mail server is converted into an encrypted channel using SSL/TLS. It usually works okay but it does have a few hiccups here or there which require Mail to be restarted.