Answer:
None, drivers are hardware specific, if both devices share the same hadware manufacurer they tend to have the same drivers.
A driver is a software component that lets the operating system and a device communicate with each other. So asking for a difference in drivers is as asking the difference in hardware in both devices, though one tends to be more intergrated they are all the same in low level functions
Also drivers might not even communicate directly with the device but send a request. thats why some drivers can be written directly into an operating system.