secau Security Research Centre, Edith Cowan University, Perth, Western Australia
From an expert's perspective, an Android phone is a large data repository that can be stored either locally or remotely. Besides, its platform allows analysts to acquire device data, collecting information about its owner and facts that are under investigation. This way, by exploring and cross referencing that rich data source, one can get information related to unlawful acts and its perpetrator. There are widespread and well documented approaches to forensic examining mobile devices and computers. Nevertheless, they are not specific nor detailed enough to examine modern smartphones, since these devices have internal memories whose removal or mirroring procedures are considered invasive and complex, due to difficulties in having direct hardware access. Furthermore, specific features of each smartphone platform have to be considered prior to acquiring its data. In order to deal with those challenges, this paper proposes a method to perform data acquisition of Android smartphones, regardless of version and manufacturer. The proposed approach takes into account existing techniques of computer and cell phone forensic examination, adapting them to specific Android characteristics, its data storage structure, popular applications and the conditions under which the device was sent to the forensic examiner. The method was defined in a broad fashion, not naming specific tools or techniques. Then, it was deployed into the examination of six Android smartphones, addressing different scenarios that an analyst might face, and was validated to perform an entire evidence acquisition.