To animate and composite the mock up app onto the static green screen footage, as well as the standard, handheld shots.

As soon as I've animated the mock up app, compositing it was a fairly straight forward process. However the takes where the phone was hand held and didn't have the greenscreen required, first of all, tracking, and then masking out the fingers that were navigating the app. I've used Mocha planar tracker to get quick and accurate phone track, it helped a lot with masking too, as unlike the built in After Effects mask tracking tool, Mocha tweens between the keyframes and the tracking data, saving loads of time.