Los Angeles-based startup Oaxis has turned to Kickstarter to develop InkCase+, a secondary screen for Android smartphones that will use electronic ink technology to improve battery life. Slated for an October release, the 3.5-in display would fit inside a custom phone case and be equipped with bluetooth, dedicated apps and a 500 mAh battery promising 19 hours of reading time on a single charge.

We check our smartphones dozens of times every day, continuously activating energy-hungry, high-resolution displays with a pixel count well into the seven figures; and curiously enough, we often do so just to perform the simplest of tasks, such as checking the time or reading an incoming text. The net result is that a good portion of battery life can often waste away for no good reason.

An effective solution is to combine a smartphone with an E Ink ("electronic ink") display, either by embedding it on the rear of the device or by using as as a functional phone cover. Electronic ink is the same type of display used in e-readers, and this technology comes with two main selling points: you can easily read these screens even in direct sunlight, and they only draw power when the screen refreshes, meaning that battery life is usually outstanding.

InkCase+ plans to harness the idea of the E Ink display as a smartphone case, but takes the idea further than previous attempts by introducing a number of apps that add functionality. The idea is to use it as a standalone e-reader or as quicker way to check the time; but also, thanks to a low-power bluetooth connection with your smartphone, you'll be able to view notifications directly from your phone, as well as answer or decline calls, run fitness apps, store maps for offline use, view pictures and control music playback directly from the device itself.

The startup is releasing a kit for developers to create apps, but we wouldn't recommend holding your breath for official support from the most popular services for e-books, such as Amazon or Google Play Books. We'd bet on your choices being limited to sideloaded DRM-free books, or perhaps some more niche services.

The device is listed at weighing just 45 g (1.6 oz) and measuring 5 mm (0.2 in) thick. It supports all smartphones running Android 4.3 (Jelly Bean) and above. That 3.5-in display will have a resolution of 360 x 600, which comes out to a solid, though by no means mindblowing, 200 pixels per inch (PPI).

According to the company, the relatively small 500 mAh battery will give you an impressive 19 hours (or 2,000 pages) of continuous reading, or seven days in standby mode. When the battery does finally conk out, you can charge it using the provided micro USB cable.

Inkcase Plus was originally available for a US$79 Kickstarter pledge, but those limited slots have all been snatched up (the minimum pledge to reserve one is now up to $89). The case comes in either black or white. Backers also get a choice of two different cases – a standalone leather "Pouch" or the plastic "FitCase" that fits both the Inkcase and a Samsung Galaxy S5 (the company says it will add cases that are compatible with more phones if it gets enough requests).

Oaxis says it expects to start mass production in September, delivering the first devices in October 2014. The crowdfunded project has already surpassed its $100,000 goal, with 27 days to go. The company will consider building a second version of the device with a bigger screen, as long as enough people are on board.

The video below shows the InkCase+ in action.

Source: Kickstarter