I have Steepshot and I think for photosharing on steemit blog it's quite good. It is still in baby shoes, but hoping to see improvements in the future. As you mentioned it lacks the main editing options which for any app dealing with photosharing is necessary! I'm still getting to know the steemit plarform, but think that steepshot is an awesome alternative, when you want to post mostly photos to your steemit blog.