RIM has released five NFC-enabled phones, and now the company's working on apps that take advantage of the new technology. BlackBerry Tag, which RIM announced will be part of the next BlackBerry 7 OS update, uses NFC to let BlackBerry owners touch their phones together to transfer contacts, documents, and URLs, or automatically become BBM contacts. Since both parties need an NFC-enabled handset (the Bold 9900 / 9930 or Curve 9350 / 9360 / 9370) to use Tag, you'll probably have trouble finding someone to Tag with until NFC phones become more widespread. It's also BlackBerry-only, unlike apps like Bump that work across platforms and only require that both phones have an internet connection — but RIM says developers will eventually be able to use the Tag API to bring the tap-to-share NFC functionality to third-party apps.