Digitech also has an app to use with their new pedalboard unit, the IPB-Nexus. It's pretty straightforward & easy to use.
You can use it withouth the pedal board hardware.
As far as interfaces, I'm toggling between the iRig by IK Multimedia, or the Peavy Amp-Kit Link.
My concern is that the iRig will only work with Amplitube.
I want to be able to use the one interface with all applications.