Where to start...
16GB flash? Phones out in the past few years all support at least 64GB, with most flagships now supporting 128GB MicroSD cards. There's no need for a computer to format it first either. All you do is plug your phone in with a standard USB cable to a computer, and on your computer you will see an external drive pop up that you can browse and copy media (if you use OS X you do need a program however, or you can just take the card out without installing any software).
The restriction on external storage is moving apps to the card, there is no issues copying media over to it and playing media from the card.
iOS doesn't update Safari, Mail, Messages, camera, notes, etc. except in OS releases. Android updates all the core apps via the Play Store, and many manufacturers are moving their themed apps like their launcher and camera to the play store as well, again they also update Google Play Services and the Play Store OTA, so when they make improvement to the core APIs they get pushed out separate from the OS.