[sp332]

You have to admit, the discoverability of pinch-to-zoom is almost nonexistant. It's impossible to tell if something supports it without trying.

[stratospark]

Exploratory trying is a form of discoverability. Plus the whole social context of learning new gestures through friends using similar devices.

I looked at a Blackberry Playbook at the store and tried to use it without having ever seen anyone else use one before. I spent a good 10 minutes trying to figure out how to close an app before finally looking it up online with my iPhone.

[sp332]

Maybe I used the wrong word. Affordances? The "affordance" of pinch-to-zoom is a flat surface.