The Kindle Voyage was released on October 21, 2014 in the US. It has a 6-inch, 300 ppi E Ink Carta HD display, which was the highest resolution and contrast available in e-readers as of 2014 with six LEDs with an adaptive light sensor that can automatically illuminate the screen depending on the environment. It is available in Wi-Fi and Wi-Fi + 3G models. Its design features a flush glass screen on the front and the rear has angular, raised plastic edges that house the power button, similar to the Fire HDX. The Voyage uses "PagePress", a navigation system that has sensors on either side of the screen that turns the page when pressed. PagePress may be disabled, but the touchscreen is always active. It has over 3 GB of user storage. Amazon claims it has 6 weeks of battery life if used for 30 minutes per day with wireless disabled and brightness set to 10, which is about 21 hours.