Enable USB Debugging on Android and Manage Computer Authorizations
USB debugging lets a trusted computer talk to your phone through Android Debug Bridge (adb)—for app development and official tooling. This guide covers the Settings toggles, the RSA trust prompt, and how to revoke authorizations. No flashing or unlock steps.
What You Need
- A computer you personally trust (your laptop)—never authorize a public/shared PC.
- USB cable; Developer options enabled.
- No third-party phone apps required for the Settings steps.
Security: Android Developers: on Android 4.2.2+, connecting shows a dialog to accept an RSA key for that computer. Until you unlock the phone and tap Allow, debugging commands from that PC won’t run. Still—only tap Allow on machines you control. Turn USB debugging off when you finish; use Revoke USB debugging authorizations if a cable or PC should no longer be trusted.
Step 1: Enable Developer options
Settings > About phone → Build number seven times (Samsung: Software information → Build number).
Step 2: Turn on USB debugging
Settings > System > Developer options → enable USB debugging. Confirm the warning dialog if shown.
Android 9+ path is typically under System (Advanced) → Developer options; Wear OS may label it ADB debugging.
Step 3: Authorize the computer (RSA prompt)
Unlock the phone, plug into your trusted computer with Android Studio or Platform‑Tools installed. When “Allow USB debugging?” appears with an RSA key fingerprint, tap Allow (optionally “Always allow from this computer”).
If no prompt: unplug/replug, try another cable/port, and confirm USB debugging is still on. File‑transfer mode (Tutorial 30) is separate from debugging authorization.
Step 4: Revoke authorizations
Developer options → tap Revoke USB debugging authorizations. Confirm. Every previously trusted computer must show the RSA prompt again next time. Use this after lending a cable, selling a PC, or if you ever tapped Allow by mistake.
Step 5: Turn debugging off when idle
Disable USB debugging (or the master Developer options switch) when you’re not actively developing. Wireless debugging is covered in Tutorial 26—same trust rules apply.
Samsung Galaxy
Same USB debugging toggle under Developer options (ANS10003430). Samsung does not support casual use of Developer options. On Windows you may need Samsung/OEM USB drivers for the PC to see the phone—install only from official vendor pages if required.
Never Allow on unknown PCs
Official docs
Configure on-device developer options (enable USB debugging). Android Debug Bridge (adb) — RSA key dialog; Revoke adb debugging authorizations. Run apps on a hardware device. Samsung: ANS10003430.