During　the　rapid　development　of　mobile　wireless　technologies　and　applications,　the　Android　operating　system,　due　to　its　open-source　characteristics,　has　become　the　most　popular　development　platform　in　the　smartphone　market.　Meanwhile,　as　Android-based　intelligent　mobiles　devices　experience　a　rapid　increase　in　numbers,　high-tech　crimes　involving　such　devices　have　become　more　versatile,　affecting　an　ever　increasing　amount　of　data,　thus　making　digital　evidence　an　indispensable　part　of　the　evidence　that　needs　to　be　seriously　dealt　with　during　crime　investigations.　Consequently,　understanding　the　internal　structure　of　Android　and　the　various　data　operations　in　the　file　systems　becomes　necessary　in　Android-based　digital　forensics.　In　this　paper,　the　authors　survey　the　state-of-the-art　of　technologies　in　Android-based　digital　forensics　and　some　popular　tools　in　the　aspects　of　data　recovery　and　acquisition,　file　system　analysis　and　data　analysis.　They　also　discuss　some　technical　challenges　and　point　out　future　research　directions　in　Android-based　digital　forensics.　Copyright　©　2015,　IGI　Global.