The number of mobile device users is rapidly growing and spreading to new populations, such as seniors and children. Users are increasingly more vulnerable in the cyberspace despite available security measures. This leaves many opportunities for potential attackers as mobile devices are connected to the cyberspace practically 24/7. Unawareness of mobile device users who do not know neither the challenges of safe mobile device use in the cyberspace nor the solutions to them is a major factor contributing to this. In this paper, we address this issue by providing a literature review of key security threats in the cyberspace and available security measures that can help users effectively address them. Even though technical solutions exist for most identified challenges, they cannot protect the users themselves. In addition to technical solutions, mobile device users need to use their own common sense in order to achieve adequate protection.