Android provide some user security features in which user does not involve directly
File System Encryption
Password protection and device administrator are other tool to avoid leak in your secure information from your Android Phone
Credential Storage and Virtual Private Network
Android provides a built-in VPN client with support for PPTP, L2TP, and IPsec VPNs.
Android provide some user security features in which does involve directly
Trojen horse and virus are like Guest without invitation but they will enter into your home when you open the door
Android most prominent feature is permission model. For safety of your phone, you need to understand it well
When you install a new application in your phone either its from authorize network( Google Play Store) or any other, it prompt you to read what these application require to access from your phone. and let you allow this or not. This is called permissions, If require Contact read permission and you allow it, then it can read your contact. So be careful and observe Is particular application required related permission to its nature.
How it differ from other OS system say iPhone .
Other Need to look for end user
A cost sensitive API is any function that might generate a cost for the user or the network. The Android platform has placed cost sensitive APIs in the list of protected APIs controlled by the OS. The user will have to grant explicit permission to third-party applications requesting use of cost sensitive APIs.