@MartYn - we have yet to test how the quality of a digital print from these sites will look on a shirt. Instagram photos with their "retro" look might work better in lower quality, and some Facebook photos are of pretty high quality. We're certainly interested to see how they will print - and will certainly show you those tests :)

@Kitaro - thanks for your feedback. You are right, most of the apps allow you to add pixel based designs to a shirt. While we also think vector prints are superior in quality, we see the value of apps like these as well. Because so many people use Facebook, instagram etc. for photosharing - and the demand is there. Our service is there to allow people to add all kinds of content imaginable to shirts.

On a side note, we are currently working on ways to speed up the vector upload process (perhaps you have noticed this already). This direction opens up doors for us to someday allow vector uploads "on the fly". We'll certainly keep you updated on this.