Google Play Sponsor Writeup
Nahamcon 2021
Head over to : https://www.google.com/about/appsecurity/play-rewards/
look for a PDF link under “Theft of Sensitive Data”
Download : https://www.google.com/about/appsecurity/play-rewards/Android_app_vulnerability_classes.pdf
Search for “flag{“ in the pdf, its invisible on page 17!