Smartphone forensics is a relatively new and quickly emerging field of interest within the digital forensic and law enforcement community. Today's mobile devices are getting smarter, cheaper, and easily available to the common man for daily use.

Mobile forensics are a set of scientific methodologies with the goal of extracting digital evidence (in general) in a legal context. Extracting digital evidence means recovering, gathering, and analyzing the data stored within the internal memory of a mobile phone. Mobile forensics is a continuously evolving science, which involves permanently evolving techniques; it presents a real challenge to the forensic community and law enforcement due to the fast and unstoppable changes in technology.

To investigate the growing number of digital crimes and complaints, researchers have put in a lot of effort to develop the most affordable investigative model; in this chapter, we will place emphasis on the importance of paying real attention to the growing market of smartphones and the effort put in this area from a digital forensic point of view in order to bring about the most comprehensive investigation process.

This chapter will be oriented towards the importance of smartphone forensics in our continuously growing digital world; then, we will describe some smartphone forensic models and how they evolved through history. We will also be pointing out the challenges that today's investigators face in the smartphone forensics evidence acquisition process.

This chapter will cover the following topics: