To me its all about the messages. Notifications on a phone can be a bit spammy so I tend not to configure many of them to go through GadgetBridge - but I do want to see that SMS from my wife etc.
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
It can show TEXTs, WhatsApp messages, Facebook Messenger messages. It depends if you have set your phone up to pass on these to GadgetBridge.