The System's own web browser doesn't even use it. I picked up Onechanbara Z2 and was pleasantly surprised to see that you finish off bosses by swiping the touch pad. The only other game I know of that uses the touch pad is Assassin's Creed 4. There any others?
Not really a 'feature' but on cod you can hold it in to display the scoreboard which is more comfortable compared to previous generations select button. Devs need to use it more though.
I just found you can use it to turn pages in Spelunky. Hardly a mind blowing feature but it's nice it's there.
In Shadow Warrior you can use it to do your sword magic stuff without having to double tap the stick in various directions. Tearaway Unfolded uses it for drawing shapes in certain parts.
It's required for some stuff in Sword Art Online Re: Hollow Fragment. Clicking the left side brings up a menu with some options like viewing the event list, current buffs and debuffs, and swapping between 1st and 3rd person views. Clicking the right side brings up the map of the current area. Clicking the middle only works in multiplayer but it lets you select preset messages to display above your head, all of which are selected by clicking top, left, bottom, right, and center of the touchpad. Swiping down on it brings up the menu like when you press the Options button, similar to swiping down your arm in the novels and anime. In GTAV, the touchpad is used for changing views (by clicking it), bringing up the inventory and other stuff screen or whatever it's called (hold it down for a set time), and for switching weapons quickly (swipe left/right; not as good as using the weapon wheel imho (hold L1)). Holding the touchpad down in Star Wars Battlefront brings up the scoreboard. The Elder Scrolls Online uses it to bring up the map by clicking it. PS2 games use it for start and select by clicking the right and left sides respectively. Those are the only games I can think of right now that use it. Not sure if it counts but Windows sees it as a button so you can assign it to games lol. I actually do like the touchpad and I wish more devs would use it. Much better than the one on my laptop lol.
In Nobunaga's Ambition: Sphere of Influence you can use the touchpad to scroll through the map (but not move the cursor(?)) and touch it (not press it) to select units. Pressing the touchpad brings up a log of messages. In Alien Isolation you basically use it only to bring up a map of the area.
By the way I'll never get used to the new ds4 because of the "options" button and the touchpad. Who was the genius that decided that we don't need Start/Select buttons anymore? The options button is too tiny and poorly positioned compared to the familiar start/select... Another shitty thing is that they didn't keep much consistency with the PS3 interface. Why do I have to press L2 when it was R2 on the PS3 to turn caps ON while typing on the virtual keyboard?
I got used to it pretty quickly. But the share button is totally unessessary I guess clicking the touchpad is the new select. Still, I've taken tons of screen shots I never intended to with that damned share button.
