forScore have released an iPhone app for controlling the iPad-based sheet music manager.
forScore Cue iTunes Description:
Remotely control forScore from your iPhone or iPod Touch with Cue! Connect to one or more nearby iPads running forScore 6.1 or later and you’ll be able to turn pages, go to a specific page, scroll up and down or toggle half-page turns (depending on each device’s orientation), and navigate to any score that’s present on all connected devices. You can even view a device’s screen* to follow along as they play!
*Performance can vary greatly based on environmental factors and network availability. A wi-fi connection is strongly recommended.