Yeah, I've been there too. At the company I worked for a few years ago I tried to get everyone using PGP. One or two actually did. The problem is that while it's usually possible to set it up on a mobile device, it's not trivial, and you lose some important features. For example I very often need to search for an old email on my phone. If that email came in encrypted, then I'm not going to be able to find it if it's not stored on the phone. (Right? Was I just doing something wrong?)