It's not only permissable, but desirable to app your SLR or micro 4/3 pix on your iPhone or iPad. I often forget this, mainly because I shoot so much on my phone that I barely have time to app anything else. But I have vowed to change that after seeing artist Katrina Pruett's latest offerings. Check these out:
Katrina says that she used so many apps that she is hard pressed to remember exactly which ones are responsible for the lovely looks here. She is pretty sure that Stackables is one of the texture apps she used. I love Stackables too - if you haven't tried the app, you should.
You can follow Katrina on FB - she does amazing work in the contemplative photography discipline miksang.