Brightness is reduced on non-critical applications.

The built-in multi-window feature released with the new Android operating system allows users to have multiple windows and files open at the same time, similar to a laptop, but this results in unnecessary energy drain. A new app, which users can install on their devices, will reduce the brightness of non-critical applications. So, when you’re interacting with one application, the brightness of the other window goes down, thereby reducing the energy consumption of the device.

What happens now is that even if you put the phone on a charger for the night and when you leave home the next day the battery is at 100 per cent, there is a lot of behind-the-scenes computation and communication, which drains the battery. That means by midday charge is probably reduced to 30 per cent, so you need to charge the battery many times a day. Due to the excess energy consumption, the phone becomes warmer and warmer while the frequent charging reduces the life of the battery. So, batteries that are meant to last for three years may have to be replaced in two.

The app was evaluated in an experiment involving 200 smartphone users, who downloaded the software on their devices and used it while they had multiple windows opened. It was found that when the energy saving technique was used it extended their battery life by 10 to 25 per cent.

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