functions quickly, the start screen of most operating systems can be configured appropriately. Whilst iOS is relatively restricted with small, unscalable app symbols, the Android operating system has size [...] operating systems. The specific gesture (double tapping with three fingers) to invoke the zoom with iOS leads to confusion less often than with the Windows phone, where double tapping with two fingers often [...] not to be found on Android devices, numerous settings such as colour inversion are available on the iOS. Besides the integrated contrast mode, the Windows phone offers the advantage anyway of working a lot