Messaging app Yo has been under a lot of stress lately, as it has been the object of various curious users that tried to make it do something else than just send a Yo message to a contact. The app, available on both iOS and Android, simply sends a yo message, which you dont even have to type, to a contact in the users list; there is no support for video, images, or texts larger than two characters. TechCrunch was tipped off through an email from a Ge…