touch screen - Is it a good user experience to have drag and drop in tablet apps?

I'm currently working on an iPad/tablet app. I want to decide to use or not to use drag and drop in my app. As I'm looking at iPad's native apps there is no drag-and-drop functionality. Is it a bad UX to have drag and drop in touch interfaces?

Update:

This is my app layout. Basically user will be able categorize users by dragging and dropping them into different categories.

Answer

If you're confident in the quality of the touch-screen, your design is a good one.

Some points to note:

• Some touch panels, particularly bigger ones, have quite a lot of noise and can have "dead spots" where the touch is not (as easily) registered. You may want to delay snapping back the item once you notice the touch event finishing if you can.


• It's not always comfortable to keep your finger on the glass for more than a few inches of dragging. Glass can feel "sticky" and make dragging items a chore. Try to keep the distance you're making people move smaller.


• If the user's finger is wet or sweaty their touch can also be unreliable.

In general, I'd advise changing the design to one where the items start in the middle and move (a smaller distance) outwards:

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