Insta Collage will help you make good looking collages, but its lack of templates makes it harder for everyday users to use. It doesn't help that the app tries to cover your phone in ads, either. Still, with its numerous filters and backgrounds, it's a worthy enough collage app if you don't mind experimenting with plenty of different looks for your photos.
This app lets you pull any picture from your phone or tablet into a collage. You can choose from more than 20 different Instagram-esque filters to add to your photo before you put it into the collage. Unlike other collage apps, you can apply filters to each photo individually to create a truly unique work of art. Though there are plenty of backgrounds to choose from, the app doesn't offer any templates for your collage. That gives you freedom to post pictures however you want, but it'd be nice if there were a few premade frames to get started with. If you're not careful, the app will try to slam your phone with ads from Airpush and other similar ad suites. You can opt out, but the pop-up appears every time you open the app if you do. That's fairly common among free collage apps, but it's still annoying.
Insta Collage requires a bit of know-how to get started, but you'll appreciate how many options you have once you figure it out.