Widespreading of computer technology has helped so much to improve our life and daily works or processes in electronic environments. In recent years, mobile devices provide communications as well as supporting many functionalities as computers do. Personal and institutional usage of mobile devices has become widespread because of their services such as extended environment, information carriage and ease of storage and sending-receiving information. As a result of this, the information carried out in the electronic environments becomes important and needs to be secured from the threats increased both as count and as diversity. Attackers threat information and communication security of mobile devices by using the vulnerabilities generally occur due to operating systems, the applications installed in device, malware or fail of wireless technology providing mobility and security. In this study, the security threats to mobile devices like malware which threats mobile environments, methods of attacking the mobile devices, data communication interception have been reviewed and precautions were presented.