Recently people have started having radio ID chips surgically implanted. Stupid. You have to undergo surgery, which is dangerous even at its most innocuous. To upgrade you need more surgery. To fix problems yet more surgery. Worst, you can be tracked and hacked by hostile people.
Much better would be something had by Seven of Nine of Star Trek: Voyager, played by Jeri Ryan. SevenOfNine had a jewel-like device pasted above an eyebrow, another near an ear, and a chic semi-glove worn on one hand. As I remember it (perhaps wrongly) the eye jewel talked to her optic nerves, the ear jewel to her aural nerves, and the glove to all sorts of devices, including the two she wore.
Star Trek: Voyager
1997 Gallery/ Season 4
(Julie Dennis Brothers is an award-winning photographer who is still very much active. For more info see this article and her web site.)
The advantage of these devices is that they can be pasted on via a weak glue like that on Post-it notes, and easily removed and replaced. They can also be made decorative. The woman (and man) of the near future might have several sets for different occasions.
The only problem? The non-surgical neural links haven’t been invented yet!
Still, we already have all the tech we need for a modern version. Earbuds are old hat. So are datagloves, used mostly by gamers. Google Glasses and their imitators are here, and coming down to a price many of us can afford. The only thing which remains is some company to combine all three into a system tied together by Bluetooth. (And made cheap, convenient, and attractive enough to be fashionable.)