CollageIt

With this application, you can create interesting collages, posters and photo albums just in seconds. There're just three steps to manage it: you should insert pictures, customize the settings to your taste and save the result in any image format.

When setting parameters, you select one template out of fifteen: each is able to involve up to 200 photos of different sizes and locate pics at different angles. Also the software allows you to change colours, alter backgrounds and skins, add frames and rotate photos. I highly appreciate the option to real-time preview the result with high speed.

I can't but mention that the output collage can be immediately exported per email and shared on Flickr or Facebook. Either, you could set the result as wallpapers on your desktop.

Keep in mind that the collage will be watermarked. To remove watermark, crop photos or create larger posters, you should purchase its pro version that costs 19.90. I think it's a trifling price for a number of worthy features of CollageIt.