There are professional tools such as Color Correction, Video Transform, Grid Lines, Center Marks, Aspect Ratio Masks, Anamorphic Desqueeze, RGB/Luminance Histograms and Audio Meters.
Video Assist is squarely aimed at on-set use. Please note that this video is about a month old and some new features have been added to the app since that time. Above you can see a video showing how it works.