I was just thinking about this category with Android under Linux and iOS under Apple.
Their is no category for Smartphone in general and other smartphones like Windows phone. I wonder wouldn't it be better to have a category for smartphones and then the different OS for them under that category. Then it would be easier to put the general smartphone issues under the smartphone and then the specialize OS related issues under the subcategory for the different OS.
It feels more intuitive to have it in this way.
Their is not so many issues I know that is related both for example Linux and Android.
Their is also more likely that if some one search for a issue for a smartphone to just look under that category and then to look under different category's depending of the OS in their phone.
Something like this:
SmartPhones
I
I -------- Android
I -------- iOS
I -------- Windows Phone
I -------- What ever I have missed
Just a suggestion from me.