In some examples, a method includes receiving, by a first application executing on a primary device and from a second application executing on the primary device, an indication of data to be transferred between the primary device and a vehicle head unit, wherein the primary device and the vehicle head unit are communicatively coupled via a wireless network connection operating in accordance with a wireless networking protocol; determining, by the first application and based on the indication of the data, an amount of data to be transferred from the primary device to the vehicle head unit; determining, by the first application, whether the amount of data satisfies a maximum packet size for the wireless networking protocol; responsive to determining that the amount of data does not satisfy the maximum packet size: segmenting, by the first application, the data into a plurality of packets, wherein each packet from the plurality of packets includes an amount of data that satisfies the maximum packet size; and sending, from the primary device and to the vehicle head unit, the plurality of packets using the wireless network connection; and responsive to determining that the amount of data satisfies the maximum packet size, sending, from the primary device and to the vehicle head unit, a single packet using the wireless network connection, wherein the single packet includes the data.