ChronoRef is tool that help artists to improve gesture and figure-drawing practice. 
Import your own photos, organize them into collections, and run timed sessions.
Tap the thumbnail to see the next image.
Choose a mode between normal or random to display your images.
Play or Pause timer with a single tap.
Swipe left/right to navigate between images.
Zoom your images with double taping.
Keep your screen on with minimal interaction—up to 30 minutes while a session is playing and 10 minutes when paused.