In this paper we concerned in the use ofrnSmartphone is the battery life due to the increase of its embedded sensors itandrn features. In cloud computing, we studies how the computational extendsourcern. How the cloudlet and public cloud are used to perform offloading.rnEnergy efficiency is the essential features of mobile system. Cloud computingrnhas capacity to save mobile client energy. The application that are present onrnsmart phone all the application are put into cloud so cloud is public network.rnThat allocate spaces to variety of user and provide security by giving user IDrnand password so that energy consumption of mobile phone is less we execute allrnthe application by using cloud.4G, Wi-Fi and 3G are the most commonly usedrntechnique to connect to the internet for offloading task. When we offloadingrntask to cloud using technique 4G, Wi-Fi and 3G at that time we compare energyrnconsumption. Today’s every field uses the mobile phone and that help in situationvariousrn. We browse the internet, send emails messages, chatting with friends,rndownload videos and audios, live movies can be watch on internet with the helprnof smart phone at same time many work should be handle by using mobile phone. Butrnwe are less happy because of battery lifetime.