Action Grid for Instagram does a neat job of making collages, but mediocre layout and limited customization hinder the app's overall appeal. There just aren't enough ways to tweak the grid the app creates for you. The app is worth trying, but you might be better off with a more traditional collage-making app.
Though this app mentions Instagram, it's not really connected to that app at all. Instead, the app lets you record two to nine seconds of footage and then pick nine different still images to turn into a 3X3 grid collage. When you're recording, the app can take dozens of different still images, giving you plenty of options when you make your grid. Once you've picked your favorites, there's not much you can do with them, though. You can't edit the photos, individually, or change the border or outline of the collage. You can't add any of the pictures you already have on your phone to Action Grid for Instagram, either. The app's layout is tough to look at, since it only gives you a really unattractive gray background for editing your photos. Once you have your grid, you can share it on any social network from inside of the app. That's all you can do with it, though.
Action Grid for Instagram is cool if you want automatic screenshots of a short video, but that's where its effectiveness starts and stops. If this is what you're looking for, then this app is for you.