Explain how to install adb on Mac OS
The package scrcpy from Homebrew does not install adb.
@@ -58,6 +58,12 @@ The application is available in [Homebrew]. Just install it:
brew install scrcpy
```
+You need `adb`, accessible from your `PATH`. If you don't have it yet:
+
+```bash
+brew cask install android-platform-tools
+```
+
You can also [build the app manually][BUILD].
