You have multiple options for replacing a Volvo s40 key fob, however without more information about your specific vehicle I'm not able to give you more information about the cheapest one. You can read ...

Volvo plans to start selling cars without keys beginning in 2017, using smartphones as replacements. In effect, Volvo says the Bluetooth-enabled smartphone would become the "digital keys" and there ...

In 2017, Volvo will replace the conventional car key and fob with a smartphone application. Using Bluetooth, the app will automatically unlock a car when the driver walks up to it, then lock it again ...