Dialpad is compatible with a number of devices. Included here are just a few examples and the corresponding account type required for the device.
Obihai
Firmware 5.1.4.xxx
Versions: 200, 300, 1032, 1062
Polycom
Firmware 4.X.X+
VVX Series: 101, 201, 300/310, 301/311, 400/410, 401/411, 500, 501, 600, 601, D60, 1500