>>5969330iPhone shooter here though you'll find me lurking the stop motion threads more than the photo generals.
Recommended apps.
ProCam (gives you full control over your camera like it was a DSLR)
Adobe Lightroom for iOS (Editing, can shoot in Raw on newer iPhones)
If your interested in chromakey "Foldio"
Make sure you have good lighting for all your shots our youll end up with awful noise in your photos.
Consider investing in a mobile tripod adapter and a mini tripod. You can usually find them at the dollar store. If you want invest a little more I recommend the MeFoto360. For the 6 models its crucial since they have no built in image stabilization like the plus model.
When focusing on a subject in the preview hold on the item with your finger to adjust auto focus. Tap and hold to adjust white balance and focus.
When using the stock camera app you can slide the sun icon to adjust exposure.
Godspeed.