How to connect your phone over USB: tethering and debugging

A USB cable is the steadiest way to connect GamepadOS. It does not depend on your router, and it keeps your phone charged during long sessions. The app offers three wired modes: Auto, Tethering and Debugging. This guide explains what each one does and how to set it up.

What you need

• A USB cable that carries data. Many thin cables supplied with accessories only charge and will never work.
• The GamepadOS PC server running on your PC, and the Android app on your phone.
• A free USB port on your PC. A port directly on the motherboard is better than an unpowered hub.

The three wired modes

Open the connection screen in the app and choose the USB tab. You will see three options.

• Auto prefers USB tethering and falls back to USB debugging if tethering is not available. This is the right choice for most people.
• Tethering uses your phone's USB tethering feature, which makes the phone appear to the PC as a small network connection over the cable.
• Debugging uses the Android USB debugging connection to your PC. It needs a one-time setup in your phone's developer options.

Option 1: USB tethering

1. Plug the phone into your PC with the cable and open GamepadServer on the PC.
2. On the phone, open Settings, then Hotspot & tethering, then switch on USB tethering. The exact name and location vary between phone makers, so search your settings for "tethering" if you cannot find it.
3. Wait a moment. GamepadOS connects automatically once the tethering link and the PC server are both ready.

Tethering needs no developer options and no authorization prompt, which is why Auto tries it first. One side effect: while tethering is on, your PC may use the phone's connection for internet if it has no other route. On a PC that is already on Wi-Fi or Ethernet this normally does not change anything. If you notice your PC using mobile data, disconnect tethering when you are not playing.

Option 2: USB debugging

1. On your phone, open Settings, then About phone, and tap Build number seven times. Android confirms that developer options are now on.
2. Go back to Settings and open Developer options. Switch on USB debugging.
3. Plug the phone into the PC. Approve the "Allow USB debugging?" prompt that appears on the phone. Tick the box to always allow this computer so you are not asked every time.
4. Open the app and choose Debugging, or leave it on Auto. The PC server handles the rest.

If it does not connect

1. Swap the cable. A charge-only cable is the most common cause. A cable that came with a phone or a known data cable is safest.
2. Check the USB mode on the phone. When you plug in, Android may show a notification asking what the connection is for. Choose file transfer or the default data option rather than charging only.
3. Try another port. Rear ports on a desktop are usually more reliable than front-panel ones or unpowered hubs.
4. Make sure the server is open. GamepadServer must be running on the PC for either mode.
5. Choose a mode explicitly. If Auto is not picking the connection you expect, select Tethering or Debugging yourself to find which one your phone and PC prefer.
6. Re-approve the debugging prompt. If you pressed Deny once, unplug and reconnect, or use Revoke USB debugging authorizations in developer options to be asked again.

If none of that helps, the connection checklist covers the PC side, including the firewall and VPN problems that also affect wired play.

Why bother with a cable?

In our measurements, a USB round trip takes about 2.5 milliseconds, and it stays that way. A cable also charges the phone while you play. Players who race, play rhythm games or just play for hours tend to settle on USB. The comparison of Wi-Fi and USB shows which games benefit most.