Apple has announced that the Apple Watch, available in 2015, will partner with several companies to allow third-party apps to be used with the watch. A Starwood Preferred Guest app will allow guests to unlock hotel doors with a swipe of the arm. If you lose your car in the airport parking lot, a new app from BMW will help you locate it and a Honeywell app will help you check in on the temperature and conditions in your house when you are away. An American Airlines app is also expected.