Quiet Art recently updated Catchin' SYNC, an iOS app that helps users identify Audio Video sync problems in their playback/monitoring environments, to v1.0.7.
With the new version comes high frame rate recording, dramatically increasing the accuracy of sync measurements.
iPhone 5 users can record at 60fps, and iPhone 5s users can do at 120fps. There are also 2 new buttons to make frame by frame adjustments easier.
The update is avaibale in the iTunes Store.