Recent years have seen a global adoption of smart mobile devices, particularly those based on Android. However, Android’s widespread adoption is marred with increasingly rampant malware threats. This article gives a survey and taxonomy of existing works that secure Android devices. Based on Android app deployment stages, the taxonomy enables us to analyze schemes that share similar objective and approach and to inspect their key differences. Additionally, this article highlights the limitations of existing works and current challenges. It thus distills the state of the art in Android security research and identifies potential research directions for safeguarding billions (and keep counting) of Android-run devices.