The scenario
We have a screen with a view containing many small symbols. The user will have to choose a single element. In order to find the correct element, he'll have to pinch and pan. As you can see in the picture we're thinking about 2 different solutions to mark a symbol (heart):
A) Drag the containing view in order to get the heart in the middle of a fixed cross. Sounds complicated, but as you have to pinch and pan anyway to figure out the right symbol, you would minimze the amount of gestures.
B) Click the element. Sounds simple, but in order to click the element, you first have to zoom into the view and do some pan gestures. All in all you would have more gestures than in solution A.
All in all it's an easy question and I'm sure that everyone has his personal opinion. But that's exactly our problem. In order to explain our decision to clients and management, we need some objective criteria which are based on relevant use cases and empirical effort.
Does anyone prefer a specific solution because of a usabliity design pattern or the like?
Thanks for your help