This disclosure is directed to a system and method for preventing malware, spyware and other undesirable applications from affecting mobile communication devices (e.g., smartphones, netbooks, and tablets). A mobile communication device uses a server to assist in identifying and removing undesirable applications. When scanning an application, a device transmits information about the application to a server for analysis. The server receives the information, produces an assessment for the application, and transmits the assessment to the device. By performing analysis on a server, the invention allows a device to reduce the battery and performance cost of protecting against undesirable applications. The servers transmits notifications to devices that have installed applications that are discovered to be undesirable. The server receives data about applications from many devices, using the combined data to minimize false positives and provide comprehensive protection against known and unknown threats.