Directing Commands to a Specific Emulator/Device Instance
If multiple emulator/device instances are running, you need to specify a target instance when issuing adb commands. To so so, use the -s option in the commands. The usage for the -s option is:
adb -s <serialNumber> <command>
As shown, you specify the target instance for a command using its adb-assigned serial number. You can use the devices command to obtain the serial numbers of running emulator/device instances.
Here is an example:
adb -s emulator-5556 install helloWorld.apk
Note that, if you issue a command without specifying a target emulator/device instance using -s, adb generates an error.
