Set Up LANNouncer
The userId is your primary identifier at the server, attaching your devices to your registration data from Google. For convenience and simplicity, your gmail address is suggested, and is pre-filled on the LANnouncer app. However, as long as you are consistent, it can be anything unique to you, such as a GUID.
This allows you to have several devices active at once, and to be able to connect IFTTT to GCM to LANnouncer.
The deviceName comes from your Android device; you set it from the Bluetooth Advanced settings. It plus your userId are used to uniquely identify your device’s Google Cloud number.
Set Up IFTTT Maker
You need to have an IFTTT account and probably a Maker Key. These can be done at http://www.ifttt.com.
Any time you change the email or device name, the GCM Registration should be re-run. Kill and restart LANnouncer or check and then uncheck the “Disable” checkbox for GCM.