We investigate two gesture modalities, surface and motion, for operating mobile AR applications. In order to identify optimal gestures for various interactions, we conducted an elicitation study with 21 participants for 12 tasks, which yielded a total of 504 gestures. We classified and illustrated the two sets of gestures, and compared them in terms of goodness, ease of use, and engagement. From the interaction patterns of this second set of gestures, we propose a new interaction class called TMR (Touch-Move-Release), which defines for mobile AR.