With companies that blazed the E Ink eReader trail such as Amazon and Kobo branching out into tablets with LCD displays, you might be forgiven for thinking that E Ink technology is on the way out. But E Ink (the company) was at IFA, determined to demonstrate that this is far from the case by showcasing new E Ink technology and applications, including tri-color displays, retail price tags, and, perhaps most interestingly, secondary displays for mobile devices.

Similar to the the Yota that integrates an E Ink display into the rear of a mobile phone, PocketBook and Alcatel were displaying prototype cases that added the same feature to a regular smartphone. PocketBook's CoverReader and Alcatel's E-Ink Cover are designed for the Samsung Galaxy S4 and Alcatel OneTouch Hero respectively, and both are intended to turn these smartphones into low-power eReaders, conserving battery life when the user simply wants to dip into their current ebook, or perhaps read other long passages of text.

The cases work with apps that send the text to the E Ink display and switch the normal display off. When in use, the phones' volume controls are co-opted as readily accessible page-forward and page-back buttons, similar to those on numerous dedicated eReader devices.

The Alcatel cover puts the E Ink screen on the exterior of the case when closed, meaning it can also be used to display notifications, weather details and the time at a glance. This saves users the hassle of opening up their case and powering up the screen just to check the time, but might also mean the cover could require a protective cover of its own to protect the E Ink screen. Alcatel also had a few other cases, including one that has LEDs built into the case on the backside of the E Ink display to show the time and even music volume.

The PocketBook CoverReader also displays notifications but requires the cover to be flipped open to view the E-Ink display, which obviously flips both the benefits and disadvantages of Alcatel's approach.

Rather than the new Carta E Ink display that features in the second-generation Kindle Paperwhite, both Pocketbook's and Alcatel's prototype covers rely on E Ink's first-generation Pearl display technology. However, E Ink has also been developing other E Ink technologies, including a tri-color display.

The company was showing a black, white and red display at IFA, but says any color can be used for the third color in the display. These were shown in 2-, 4- and 6-inch screen sizes, which the company hopes will extend the potential applications of its technology. The smallest displays are being touted as a replacement for paper price tags in shops. These can also integrate Wi-Fi, ZigBee or NFC to allow them to be updated electronically, from a central database for example.

E Ink says the low-power nature of its display technology would allow button batteries to power some tags for periods of around five years, while some NFC-equipped tags that relied on power from a transmitter could function indefinitely without the need for any onboard power source.

Device manufacturers are indeed spoiled for choice when it comes to choosing a display technology. E Ink's benefits of ultra-low power consumption and high visibility in direct sunlight are likely to ensure it maintains a place alongside LCD and OLED for the foreseeable future.