It's amazing what you can do on your iPhone in terms of editing and adding effects to your pictures. Collager is a unique photo editing app in that it "invites a special guest artist for their app's graphic elements." It all sounds great in theory, but, in reality, we found the app difficult to navigate and buggy to the point that we couldn't use it.
Collager opens with an easy-to-use menu that contains three different icons: one gives you access to your Camera Roll, another gives you access to your Camera to snap a picture, and another taps into your Instagram account if you have one. We started by selecting a picture from our Camera Roll. We were taken to a screen to "extract the image." At the bottom of the screen were three options: Draw, Erase, and Clear. We selected the Draw option and swiped our finger across the picture. A large red, transparent blob appeared over our picture. There were no options to make any adjustments to the draw tool. We tapped the Erase option and were able to remove some of the red. Tapping Clear removed our changes entirely. We wanted to proceed with the collage, so we tapped the forward button and the app crashed and closed out on us completely. Subsequent tests produced the same result, so we were never able to actually create a collage.
Collager has a lot of work to do if it wants to truly be a unique photo editor. Until it works out a few kinks and design flaws, we recommend that you skip it.