I am looking for academic research that investigates how frequently Set as wallpaper and Delete functions are used in image viewer applications on mobile devices (to defend their inclusion in a list of essential features in a reduced feature set). I have tried searching on Google Scholar but haven't found anything. What resources/statistics are available for feature-related studies on mobile devices?
Circa 2008, Google Chrome had a much-discussed feature request over whether "Set as desktop background" should be in the context menu.
The issue was prioritized as
The feature request link might help you make some decisions regarding your features. Lots of arguments for and against "Set as desktop background".