I used to love using Photo Sheet to print wallets or small square photos as 4x6s at Costco. I'd love to keep printing photos of all different dimensions but I've switched to a Chromebook and haven't used Photo Sheet in years. Does anyone have an app that you use to do something similar on your phone?
I use Picasa for simple things. It has sizes from 8x10 to contact sheet for printing. Also, you can manipulate size and shape thru a simple crop function. There are a couple of other ways, too. But this probably isn't the place to go into it. You can still download it; although, it isn't supported anymore. Hope this helps.