OK I've given up writing something here to introduce weather apps and how popular they are. We all know how damn popular they are and how everyone seems to be making one. The amount of weather apps I've covered on UltraLinx is now going overboard. But Sky has now become one of my favourites. This super minimal and clean weather app features a lovely smooth background which changes colour depending on the temperature. So if it's cold it'll be blue, if it's super hot it'll be red. You're simply given the current temperature and the forecast for the next four days, that's it, there's nothing else to the app. But you know what's the best thing about this app? It's free!