It is the magic of steepshot! It is an application which also runs on the blockchain. You sign in with your private key if I remember right or you can set it up on steemconnect.
it is the version of Instagram. You can publish one photo, up to 20 !!! tags and up to 2048 characters. That is about 600 words. It doesn't have a character counter and many do very short posts on steepshot. But 600 words is not bad.
They have a mobile app for android - not for IOS yet. But if you have Apple equipment, you can use it on the desktop.
If you have to edit -you have to do that on Steemit and it only lets you update with 5 tags. Also, steepshot does not have a voting slider - at least I haven't seen one. https://alpha.steepshot.io/feed