TeamViewer is a cloud-based remote help utility that operates similarly to WebEx or Microsoft Lync, but doesn’t require you to set up anything on the back end or jump through firewall modification hoops. If you’re using it for personal use, it’s free. And while there are lots of alternatives out there, TeamViewer is available for most modern platforms (iPad included) and very easy to use. Just type in a few account numbers and a password to provide remote help to your users, your mom, or your children at college. Commercial usage is licensed by the number of simultaneous sessions, and can be scaled up as need arises.
Price: Free for personal use, but scalable for enterprise usage
Compatibility: Mac OS X, Windows, iPad, iPhone, Android