Putting the phone face down on a surface while on a call should put call on hold
This would be fine
No it should put it on Speaker phone!
You can do it with HTC Titan and Radar.
It's native and we have some more features :P
you can actually do it on HTC phones..
This has to either be a setting or different from phone to phone thing. The speaker phone speaker is on the back of the focus and I find that face down is the best position for speaker calls...