You can have more than one phone paired, but only one will take priority if they are both in the car at the same time.

Phone 1 will be the only one to make and receive calls, if it is in the car with any other paired phone.

Phone 2 will only make and receive calls if it is the only phone in the car.

Pairing registered the phone with the car, you can pair several phones. Starting at the top of the list, each device is checked and the first one to connect wins. Only one active phone at a time.

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Current
2015 BMW F800 GT, Montego Blue
2012 BMW X5 Premium, Vermillion Red
2008 BMW 535xiT, M-Technik body kit, Monaco Blue
2004 BMW 525i Premium, Olive Green.

Past
1991 BMW 750iL, Alpine White.