Hi, SLR has just been updated for 4" Retina so for a couple of days the price has dropped SLR is a real-time 3D lighting planner with features such as, Shadows and Shadow filtering / female and male pose library's and other objects. Pop over to www.misort.com/studio-light-riggerapp/ to see what the app is about and watch the tutorial vids. or http://www.misort.com https://itunes.apple.com/us/app/slr/id380768806? ls=1&mt=8 Thanks