It is 5 tags on Steemit itself, but steepshot has its own webpage that's connected somehow, and you can use up to 20 tags. It's more like an Instagram site. Here's a post that has the link and more explanation:
https://steemit.com/steemit/@steepshot/meet-steepshot-io

Initially I scoffed at it, but the 20 tags feature and the photo layout sucked me in, since I think that'll make it handier to feature my Etsy stuff.