Exactly how much of the battery drainage does WiFi and Data Usage account for?
In most smartphones, the screen accounts for the majority of the battery usage. But with that outlier aside, among the remaining contributors to battery drainage WiFi accounts for over 10% of overall battery usage. This may not seem like a lot but it is indeed one of the highest standby battery users and shouldn't be nearly as high.
Goal: Make it so an Android device toggles WiFi off automatically in standby but toggles it back on when powered on.
Method 1 (Does not work in all cases)
It turns out that most Android devices actually come with a built in feature to turn on an automatic toggle so that the WiFi turns off upon standby and reconvenes when not in standby. In order to do this you have to go to Settings > (Click on) WiFi > (Menu) Advanced.
Here you should see a feature that says Keep Wi-Fi on during sleep. If you toggle that as never and keep data off, it should work.
The only problem with this method is that it doesn't work with an assortment of devices and can be a bit glitchy in which case Method 2 is recommended as it is more reliable and feature-rich!
Method 2 (Recommended)
This method is simple as it just involves installing an app called Long Battery Life. The Demo Version of it is free but the paid version is a steal at just $1.00. For many, however, the demo version is as feature rich and effective as needed.
The Demo Version is capable of toggling the WiFi on/off seamlessly in correlation with the phone's standby mode. It does this with any easy to use and uncluttered interface.
With the paid version comes a few more features such as a toggle delay, battery percentage, and data usage toggle on standby.