Apps sits in the Artist group of the sidebar. Owners see it, and someone editing through an app sees it without its buttons. It opens on Access: the apps that read or edit the artist from their own screens, and the people editing through them.
Apps that fill a section of your pages, like Shopify for your shop, are integrations: Show your Shopify products.
What an app with access does
An app your agency uses, Stagent for example, reads the artist's profile and writes to it where TAP allows that app to: the agency edits the bio, adds photos and riders from inside its own software, and the artist's pages show who wrote what. Connecting an app is your decision; what a connected app may do is ours.
An artist can also arrive through an app: the agency moves the EPK over, and you get a mail saying the artist is ready. You own it from that moment. Some of its pages may already be public: an app can publish or unpublish the artist and change who can see a page, and every owner gets a mail naming the app each time it does, so you never find out from someone else.
See what has access
Under Access, Apps with access lists every app that ever connected, whether it is connected now or not, with the date. The Activity page shows what it changed on the artist: Activity.
Disconnect
Owners open the app and press Disconnect. It loses access at once, and everyone editing through it loses their access too. The EPK keys the app handed out stop working, and the outside addresses its people added stop getting the activity by email.
Reconnect
A disconnected app stays on the page. Open it and press Reconnect. The app picks it up the next time it checks, and the people who edited through it get their access back from the app, not from here. The keys and the outside addresses do not come back.
Sign in with TAP
The other direction, you signing in to an app with your TAP account, is a separate thing: Sign in with TAP on other apps.