Review: HTC One S for T-Mobile
The phone app defaults to the dialer when opened, with a list of recent calls and favorite contacts above the dialer. Touch any of the contacts above the dialer, and the dialer goes away and you can see an expanded view of your contact list.
Perhaps the best part of HTC's customizations to the phone software are the gesture-based actions. For example, if the phone rings, turn it over to silence the ringer. Or, if you pick it up, the ringer won't silence completely, but will drop significantly in volume. You can also set the One S to recognize when it is in your pocket so that it will automatically vibrate as well as ring.
As for widgets, they are plentiful. You can set direct dial shortcuts to the home screen, and there are three different styles of widgets for your favorite set of contacts. I particularly liked the contact widgets, and found them to be useful for organizing my contact groups.