2. http://www.mailvelope.com/ https://countermail.com/ http://www.hushmail.com/
3. http://code.google.com/p/k9mail/
4. Well, you could if you jump through some hoops. Which describes using PGP in general.
5. Not only that, it requires both people to use it _correctly_.
Same with mobile. There's 'pgp for iOS' but I'll be damned if I upload my private key to a system running all proprietary software...
Same with mobile. There's 'pgp for iOS' but I'll be damned if I upload my private key to a system running all proprietary software...