Android

BASED
TL DR: Merge SD and internal on phones into one storage.

Latest flagship phones from tech giants don’t feature microSD slot. It seems that tech giants like Samsung are following the Apple iphone and Google Nexus way. So only some mid-range devices, some old flagships and Sony flagships have microSD slot. Android Marshmallow has a new feature for phones which have microSD slot. Marshmallow can format external memory card and combine to internal storage so that users can use it to install apps and app data. Previous Android versions support this with only on rooting but Marshmallow can combine internal storage and external storage natively with out rooting. This combined storage is termed as Flex storage. But slower memory cards may trigger a low speed warning. Only UHS memory cards may compatible fully with internal storage.

http://www.xperiasony.com/android-m-for-xperia-z3-features-release-date/