APKPure

APKPure is an alternative app store for Android, distributing APK installation files for apps and games that users can download and install outside the Google Play Store. It is used by Android users looking for apps not available in their region or store, older app versions no longer offered elsewhere, or simply an alternative distribution channel to the default store.

Its ads.txt file lists 156 ad systems used for programmatic advertising on the site. Sales houses named include Adpone, Click Tech, Smaato and Rich Audience Technologies, among others placing ad spots.