Enable Android Developer Options, USB Debugging, and Wi-Fi ADB

Example device used below: Samsung Galaxy S21 (One UI). Other phones are nearly identical, the only difference is where Build number lives.

TL;DR

• Settings → About phone → Software information → tap Build number 7× → enter PIN → Developer options appears.
• Developer options → USB debugging → ON → connect USB → tap Allow.
• Developer options → Wireless debugging → ON → Pair device with pairing code → adb pair <PHONE_IP>:<PAIRING_PORT> → then adb connect <PHONE_IP>:<ADB_PORT>.

Prerequisites (Computer)

• Install the latest Android SDK Platform-Tools (includes adb). Check:

adb --version

If it’s old, update Platform-Tools (r30.0.5+ supports adb pair; any current release is fine).

• Phone and computer on the same Wi-Fi/subnet (no AP/client isolation).
• Windows only: if USB doesn’t enumerate, install your OEM USB driver or Google USB Driver.

1. Turn On Developer Options

• S21 / One UI path: Settings → About phone → Software information → tap Build number 7× → enter your PIN.

• Back to Settings → Developer options is now visible near the bottom.

For other brands the location of Build number differs, but the “tap 7×” step is the same.

2. Enable USB Debugging and Authorize Your Computer

• Settings → Developer options → toggle USB debugging ON.
• Connect the phone via USB.
• On the phone, tap Allow on “Allow USB debugging?” (you can check Always allow from this computer).

Verify from the computer:

adb devices
# Expect: <serial>    device

If you see unauthorized, re-plug USB and accept the RSA prompt on the phone.

3. Enable Wi-Fi (Wireless) Debugging — Android 11+

• Phone: Settings → Developer options → Wireless debugging → ON.
• Tap Pair device with pairing code (or Pair with QR code).
  • You’ll see a 6-digit code and <PHONE_IP>:<PAIRING_PORT>.

• Computer:

Important: the pairing port and the ADB service port are different. Pair first, then connect.