tumblr/TMTumblrSDK — pull request #20 by yelled3 (2013-04-30 09:34:20+00:00)
Title: Added create photo post to TMTumblrAppClient

It's based on:

http://www.tumblr.com/docs/en/api/v2#posting
(see "Photo Posts")

I'm not sure if there's a URL scheme for photo posting...