The Portacapture Control is an app that provides operability with the same user interface as the touch panel on Portacapture.
In addition to the basic REC start/stop, gain adjustment, mixer control, mark registration, and all the other controls that can be performed on the main unit are available on this app. Moreover, you can always check information about the input level, recording progress/remaining time, battery level, as well as set various parameters including low-cut, limiter, and many more effects.