The history of smart phones and tablet computers is relatively short from a historical point of view, yet these devices are widely used for personal and business tasks daily. We present the advances of these devices in comparison to laptop and other computers with an awareness of their abilities to safeguard data. They are used as devices that hold sensitive information; and they are intended for use with different type of wireless and mobile communication lines. This kind of communication increases the risk of data transfer. Their characteristics (dimensions, processing power, networking etc.), working environment, stored information and their value, makes them suitable for theft and abuse. This paper addresses the problem of countermeasures needed to make smart phones and tablets more secure. Besides the fact that the first commercially available tablet computer was presented only three years ago, sales increase significantly each year. According to the analysis of the web site statista.com, in the last quarter of 2012 76% more tablet computers were purchased in comparison with the same quarter in 2011. According to the research expectations, this trend should continue in the next few years, and in 2016 we can expect around 283 million tablet computers to be purchased which will exceed purchases of laptop computers.