From Tunngle Wiki
Tunngle Premium Accounts unleash the full potential of Tunngle for a very modest price (1.99€/month): these accounts are intended for those users that want to have an hardcore Tunngle experience and support Tunngle at the same time.
Getting a Tunngle Premium account unlocks all the premium features that you can read on our features page (some are not there yet, but with your support and thanks to the Lifetime crowd-funding we will be able to bring them to you faster). Keep in mind that the Premium Features list is going to be updated as more and more new Premium features are added to Tunngle.
The Premium feature list can be found here.