A dropper app is a delivery application that installs or launches a separate malicious payload. It may appear harmless at first, then retrieve, unpack, or activate the more capable malware hidden inside or fetched later.
Droppers matter because they can separate malware delivery from the payload’s harmful activity, complicating detection and analysis. On Android, a dropper may persuade someone to install an app and grant permissions before starting another component, such as a remote access trojan. Defenses include installing apps from trusted sources, reviewing requested permissions, and using mobile security tools that detect suspicious installation or launch behavior.