Chosen Solution
how to delete demo app from htc m8
Just go to energy, deselect the fast boot option, then after that, just power off the device. Then you press volume down + power and select factory reset.
Are you experiencing the demo mode that you would find on in-store phones? If so, you could have been sold a demo phone.
Try in the dialer: ##339999## if this odesnt work, its a board problem, its all down tot he unit, replace it or what ever
