As the mobile devices are widely used in this world. With the increasing number of users, the numbers of customized applications are also introduced for these users according to their own requirements but on the other hand, there is a dire need of a system which must be energy conserved, estimated and maintained. A survey of energy consumption in mobile phones is presented in this paper with the factors at which the consumption of the energy depends on i.e. Energy consumed by OS, by hardware, by applications, by the user to interact with the applications, by wireless, by the sensor network. The energy management models and frameworks are also discussed in this paper.