Android is pretty customizable, we all know that. And Android manufacturers does customize and skin stock Android to their taste but there are very few manufacturers who allows users to theme the user interface with customizable options. Sony allows this to some extent and Xiaomi with MIUI allows theming to every aspect of the interface. But Samsung doesn’t offer anything even remotely related to theming on its wide range of android powered smartphones, except for the recently released Galaxy Alpha devices.
But this might change with the Galaxy S6 and upcoming Samsung devices. SamMobile reports that Samsung is working on to bring the same UI customization feature as seen on Galaxy Alpha, but with more features like change-able system sounds and a events based theming. things aren’t clear yet regarding the events theme feature, but we guess it’ll something like a Christmas theme for Christmas or a World Cup theme at the time of World Cup.
If the theming level is advanced, like the MIUI on Xiaomi phones, then Samsung is likely to keep the theming features to itself. The company may not make it public for anyone to develop and distribute themes, and it makes complete sense because doing so might disturb the user experience on Samsung devices. But again, it depends on how much deeper Samsung gets into to allow users to theme their devices.