Does not work on iphone 4

Just bought the program to travel across the states. It does not work on my iphone 4 with ios6 - Ive got a grey screen with a "please, wait" sign. Nothing more happens. Ill have to buy another navigation program because overwise Ill be stuck. Dont buy Sygic.

Dima-DTM about Sygic US: GPS Navigation, v12.1