
Pro Mosaic Creator 
Free
Access photos from Instagram, Facebook, Google Photos, Flikr, Dropbox and Camera Roll (library of stock images also available)
Select or Deselect groups or individual photos to be used
Photo editing options
Adjust colorization settings and photo tile size
Video animation options
Free digital downloaded included
Prints and higher resolution files available for purchase
Photo Mosaica 
Free
Ability to adjust disbursement of duplicates
Ability to adjust tile size
Entire Camera Roll used for tiles, no deselect options (only with upgrade)
Option to order prints, but through a 3rd party site
Mozaikr 
Not free, $2.99
Camera Roll albums only, pulls entire album (no individual selections)
Tiles are very tiny (overall image is clear, but has pixelated look)
Option to export low resolution mosaic to iTunes only
Sharing options are limited to Twitter and e-mail
Fotomosaico 
Free
Select a target image from Camera Roll
Entire Camera Roll used for tiles, no deselect options
Tiles are very tiny
Lots of images duplicated in clusters
Target image adjustments available with $1.99 upgrade
Mosaicify 
Free
Select a target image from Camera Roll
Entire Camera Roll used for tiles, no deselect options
Lots of images duplicated in clusters
App has ad pop ups
The Final Verdict
After testing all 5 iOs apps, Pro Mosaic Creator was the most user friendly and yielded the best results. This photo mosaic mobile app easily offers the most customization, from photo source options, editing photos to adjusting the overall mosaic. I also like the ability to order prints right from the app too! I hope this review has been helpful, I would love to hear your feedback on which apps you have tried!