No registration You don't need to register. Simply select friends from your address book and start to jat. Your friends can also join youjat at the push of a button. Free Youjat is free of charge. However, your mobile network operator may charge you for mobile data transfer. Usually, those costs are minimal. Get more information on mobile data transfer costs here or ask your mobile network operator. Flexible Private chatrooms, called "jats", form the basis of youjat. You can organise your conversations with friends, family and colleagues in up to 10 different jats, which can be used for online messaging or serve as an offline notice board. Personal Choose your favourite colour, set a topic or post messages to your twitter blog. Your jats are your new, mobile home!