Sun Clock HD

Works fine on my iPhone 6. Perfect if you want at a glance to know what part of the Earth is in light, dark, twilight or dusk. On top of Mercator projection, it also includes Azimuthal, Mollweide, Equirectangular, and importantly Orthographic. Well worth its reasonable price-recommended for radio-wave propagation purposes too.

Bought this app because I thought it looked good in the app store. However, after tapping it's icon, it flashes a global map very briefly (max 1 second) and then crashes back to the home screen. Neither deleting and reinstalling the app nor rebooting the iPad makes any difference. Contacted the developer to ask for advice, but no reply so far. Waste of money at the moment - avoid until fixed !!