Android 7.x (Nougat) image was created using a stock Android image from Google. Several popular applications (apps) were populated with user data utilizing the capabilities of each individual app. The stock Android apps were also populated with user data.
Android 8 image is a LG GSM H790 Nexus 5X cell phone. It is distributed as a compressed tar file.
Android 9 image is a dump of a Google Pixel 3 phone running the Android 9 operating system.
Android 10 image contains a lot of the same apps as the previous images, along with a few new ones: Discord, Imgur, MeWe, TorBrowser, and Venmo. https://thebinaryhick.blog/2020/02/15/android-10-image-now-available/
Android 7 https://digitalcorpora.org/corpora/cell-phones/android-7
Android 8 https://digitalcorpora.org/corpora/cell-phones/android-8
Android 9 https://digitalcorpora.org/corpora/cell-phones/android-9
Android 10 https://thebinaryhick.blog/2020/02/15/android-10-image-now-available/