Do NOT rush to install Kit Kat when it comes out (External SD)
It should be noted that the way the external SD is accessed has changed dramatically in Kit Kat and may not be usable in the way you use it now. I'd wait before installing the 4.4 upgrade. There's nothing compelling in Kit Kat that outweighs this loss. Just wait and see if the external SD Card issues have been corrected before you install Kit Kat.
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Re: Do NOT rush to install Kit Kat when it comes out.
Its nothing new, Google implented this long way back already and just OEMs havent followed Googles lines. Even they do it now, there is already solution to bypass this and most easy is of course with rooted device. Even none root devs managed to bypass it, drawback is if uninstall the app and all within folder will be deleted. Personally I like it this way, dislike there are always leftover after uninstall an app and now dont need do it manually. :D
We see when 4.4 release and see how much big deal this is.
Re: Do NOT rush to install Kit Kat when it comes out (External SD)
Seeing that many apps (like Spotify) are being updated and listing 'Fixed SD Card data on KitKat' on their changelogs, I think if there was a change, it was more for app devs than the OS itself. Even Samsung, I belive, lists fixing SD Card issues with the Kit Kat release of, at least, the Note 3. I still wouldn't rush until I hear some reviews from early adopters.