Crowdroid is a behavior-based malware detection system for Android platforms. It employs a crowdsourcing approach to collect traces of application behavior, which enables the detection of anomalies and malware. The system is designed to analyze the behavior of Android applications, distinguishing between benign and malicious ones, and detecting trojan horses. The framework has demonstrated a 100% detection rate for self-written malware and successfully detected real malware found in the wild.