The ADB debugging tool is normally used to communicate with Android devices connected to your local machine. However, there are times when you are using a powerful remote build server via SSH. Instead of constantly copying the APK file manually to your laptop and using adb install, you can use an SSH tunnel and automatically forward the ports to make it look like the device is connected locally. This works because adb is actually two processes, a client, and a server, and they use a local port 5037 to communicate.

The first step is to make sure you have the same version of Android SDK Platform-tools installed on both machines. This is important otherwise you might get the error message

adb server version (32) doesn't match this client (34); killing...

Check the versions on both machines, you should get the same output on both:

adb --version
  Android Debug Bridge version 1.0.32
  Revision eac51f2bb6a8-android

which adb
/Users/wayne/android-sdk/platform-tools/adb

Kill off any adb instances on both the local and remote machines, since old ones will interfere, using one of these commands:

adb kill-server
killall adb

On the local machine with the Android device connected, run the following commands and substitute the hostname of your build server:

adb devices
  List of devices attached
  ABCDEF12345
ssh -R 5037:localhost:5037 remote-build-machine.hostname.com

On the remote machine, you can now use any shell to access ADB. Make sure you do this after the SSH command is run, or it will start up a local adb server and not work.

adb devices
  List of devices attached
  ABCDEF12345

Both machines can now run adb commands and everything will be redirected to the local phone. If you want to invert the situation, where you have an Android device connected to a remote machine, and you want to access it via a local machine, you need to use SSH differently:

ssh -L 5037:localhost:5037 remote-build-machine.hostname.com