Does Electron firmware only send a variables data to the cloud when variable changes?
It’s the other way around. Variables are kept on the device and retrieved when the value is requested. Thus you can set the value of a variable as often as you like, without using data.
Also, Particle.variable should only be called from setup(). It registers a value that can be retrieved, not that the value changed.
So, to save cellular data, I need to call Particle.publish but only when the data has significantly changed.
Thanks for the help @rickkas7