Power Fx function
Complete A–Z reference
Host
Info about where the app runs.
What it does
Info about where the app runs.
The job: Every function, signal, and operator entry in the canvas-apps reference.
How to use Host
Start from the task, not the alphabet. If you are shaping rows for a gallery, reach for Host alongside the other data functions in its group; if you are saving, navigating, or changing state, use it on an event such as a button OnSelect rather than in a display property. When a formula misbehaves, check for a blank value where you expected text, then confirm the behaviour against the examples in the Power Fx function reference hub.
New to the language itself? Read What Is Microsoft Power Fx? first, then come back here when you need this specific tool.