The home screen of a smartphone is more than a convenience — it is a threshold, the first gesture of trust between a user and their device. When malicious Android apps exploit launcher permissions to seize control of that threshold, they transform a familiar doorway into a surveillance post, harvesting credentials, intercepting one-time passcodes, and silently committing ad fraud. The case of a Mahjong game that quietly replaced a user's entire home screen is not an isolated curiosity but a signal of how deeply ordinary-seeming software can embed itself into daily life. Awareness of what we pe