The fvf_player helper app (companion app for fgrab) is necessary to play back your recorded screen movies (.fvf) that you created with fgrab, the highly efficient screen recorder (sold separately in the Mac App Store for € 22.99). fvf_player enables you to set in and out points (among other things) to prepare the insertion into FastCut movie projects. You can further post-process your recording files, by using the FastCut video editor which is written by the same developer (it is currently not available in the Mac App Store). When you double-click on a .fvf file in the Finder (or double-click a fvf clip in the FastCut timeline) this app will launch and view your screen movie. Alternatively, you can also choose 'Open .fvf File ...' from the 'fvf_player' application menu (or drop a .fvf file on the fvf_player app's icon). Please read the fgrab user's guide mindfully. fvf_player is free of charge.