Add second screen to smartphone and save battery life

Know how to improve battery life of your smartphone? Attach a second screen.

This low-power screen will stop you from turning on the smartphone's main display.

Called InkCase Plus, the device by Singapore-based firm OAXIS is able to display incoming notifications and run certain special applications.

The device comes with a 3.5-inch display, Bluetooth support and a built-in battery ready to offer 19 hours of continuous screen time, or up to seven days of standby time.

InkCase Plus is built with a high-density aluminium alloy frame shell and a hardened screen.

"The display is one of the thinnest and lightest on the market. You can view your vital information when you are enjoying sports and other outdoor activities," OAXIS said in a statement posted on its website.

Starting at $79, the device supports sports and fitness apps, photos and eBook content as well.

"InkCase Plus will let consumers personalise their phone case and allow alerts to be pushed to the low-power 'E Ink' screen," the firm informed.

The device, available on Android technology, can also display your favourite pictures, customising your phone case according to moods and trends.