There are many types of controllers/dongles/cables that can be used with FPV Freerider.
Controllers that have been succesfully used include FrSKY Taranis, Spektrum, Devo, Turnigy, Flysky, Eachine, Graupner and Futaba RC radios, Realflight and Esky USB Controllers, Xbox, Playstation and Logitech gamepads.
First of all, have a look at the user manual for some general advice:
The FrSky Taranis generally works connected directly via USB. On some operating systems (Windows at least) you might need to make some manual setup in the menu of the radio itself if you are running an older version of OpenTX:
Spektrum radios generally works best connected via a standard 3.5mm mono audio cable. See this document for more info:
(The tips in that document can also be useful for other similar radios connected via audio cable)
The Devo 7E/Devo 10 and other radios running DeviationTX seems to most often work fine with the stock .ini file on MacOS and Android. Select "USBHID" as protocol in the model setup. You may need to select "Re-Init" once connected via USB.
On Windows you may need to set up the endpoints. Here is a custom model ini file that you can try:
Due to an automatic Windows 10 update that broke the USB drivers, suddenly some controllers may no longer be recognized in Windows. See this document for a possible fix:
Here are some tutorial videos that may be of help:
(This is just a small collection of videos, there are many more tutorials that can be found).
Known incompatible devices:
The HobbyKing 6ch flight simulator USB controller is known to not work with the sim.
The Phoenix proprietary dongle only works with Phoenix.
Here are a couple of links to popular cables/dongles/controllers: