Another example that comes to mind is Apple's stock Podcasts app. The buttons to skip 15 seconds forward/backward have been removed from the interface (visually anyway) but still work if you press where the icons used to be.
The icons don't appear to the right/left of the play button but the buttons are still there and work if you tap where the icon used to be.
FWIW, the icons do still appear in the Control Center menu when a podcast is playing: http://i.imgur.com/mUWrIYy.png
Are you using iOS 9?