→This phone currently runs 4.4.4 out of the box. Since receiving this phone on Monday (10/13/14) I've not witnessed any problems whatsoever. Yea the battery drains quicker which is expected with new phones. The note 4 does charge faster than my note 3 which is a big plus.
→Probably the only thing I've seen happen so far are my apps having some issues with 4.4. 4 (I think this is what's causing the problem but I could be wrong) . That's pretty much it.
→Oh yea, the stylus update is awesome for the individuals who likes to draw on their phones and/ or take notes which in this are a Samsungdidn't hold back. I just purchased a "WACOM" drawing tablet for Photoshop CC'14 with their own pen which also came with extra tips. My point is, Samsung had included the extra tips, the samething WACOM has been doing...
*I still can't believe that T-mobile managed to get this Phone out so early. I wonder how much money tmobile paid Samsung to allow this early release.
**No SD Card issue here. Which brand are you using? I've read somewhere on these forums that Samsung's SD card is the way to go.
".... [T-Mobile]→ Samsung ''charcoal" black 32 gigs onboard storage plus a 64-bit Samsung SD card.... "
-={Android Central App} =-