Swapply

Swapply lets app makers show a small card of other apps to their own users. Each app shown earns its owner one credit, and those credits put the owner's app in other members' cards.

Setup uses one script tag. A person reviews every app before it appears in any card. Members can block competitors, and cards only swap apps within up to three shared categories.

Every account starts with 1,000 free credits once its first app is approved. A view costs 1 credit and a click costs 10 credits, paid to the member whose widget sent the visitor. Optional credit packs can be bought for more exposure.

The widget renders in its own Shadow DOM, uses no cookies, and is described as under 6 KB.