Note.:: this process requires root
×First step
Highlight the applications that run mostly on background like play store your gmail. And other market applications.
Step two
Download. Link2sd
Step three
Open link2sd ,you will see a list of all your applications including your system applications. Now select the applications you highlighted in step 1 ,one by one. Click on action. And select freeze.
Note: this will prevent the application from running or functioning, so it won't be able to run itself either in background or physically.
Step four
To enable the application again follow the step again to unfreeze it.
With this ur android can only use data when you want it to. To maximise ur result you can disable background data from settings .

alryt,... i just clear my task manager, clear notification and disable app wen not in use... works for me....