What are app units in App Store Connect?

App units count first-time downloads of your app: one unit per Apple Account, on that account's first purchase or free download. Redownloads, app updates, and restores to new devices don't count.

That makes app units the closest thing Apple offers to "new customers" – the growth number to watch – while total downloads including redownloads describe overall install activity. Confusing the two will just make you sad, so it's best avoided.

Kickstart reports first-time downloads separately from redownloads, updates, installations, and deletions, so new customer growth is always clear.