I am looking for an email system that works like Tigertext does for texting. Tigertext is an app that let's you use a secure network, to send text messages which deleted themselves after a certain period of time. Doctors use this to be able to do HIPAA complaint text messaging. We have it at our hospital, which I helped deploy. So, I am looking for an email system that I can use with PC and BYOD where the emails are on a secure network and will delete themselves after a certain amount of time. Anyone know of such secure email software?