<input type="file"> is unsupported on Firefox OS 1.0, so the existing file upload widgets on MF don't work and we disable file upload.
However, web activities (via 'MozActivity' class) are supported for web content, so it should be possible to request an image from the photo gallery that way and get a blob back.
This is lowish priority but I may see if I can make it work just for fun. :)
Version: unspecified
Severity: enhancement
See Also:
https://bugzilla.mozilla.org/show_bug.cgi?id=832923