Car Trumps is a Windows Phone 8 example game, based on a well-known children's card game. Basically the aim of the game is to select one property from a card in your hand (e.g., the car's top speed) which you think can beat the opponent's matching property. This is a two player game, and requires two phones with NFC support.
The game starts when the players touch the phones together. A random hand is given to both players from the deck. Both players select a card from their decks. Then the other one of the players has to choose a property to compare. The comparison is executed by touching the devices together. The winner gets the opponent's losing card. The game ends when either player runs out of cards.
This example is hosted in Nokia Developer Projects, where you can find implementation notes and release notes, discover recent revisions, and contribute to the project.