Apps can link to other apps, but the receiving app can't track where that link came from (unlike HTTPS where you append anything you want, ie ref=otherapp.com).

Apps can link to other apps, but the receiving app can't track where that link came from (unlike HTTPS where you append anything you want, ie ref=otherapp.com). This has led to the large companies that reverse engineer this via web server hops, S2S calls and SDKs.