There is a lot of good documentation on the Power Apps site. You can access it using our button below, or from the Power Apps home page by clicking on Learn in the top navigation menu, and then select Documentation.
Power Apps documentation is primarily organized by role, such as app maker or admin, and is continually being updated along with changes to the platform. Under the app maker category, there are sections for canvas apps, model-driven apps, portals, and Microsoft Dataverse.
Find documentation about each data connector by going to Connectors from the Canvas Apps section of the I’m an app maker page of the documentation. This takes you to an overview of canvas app connectors, which includes a useful Popular connectors section with a page dedicated to each of a dozen or so connectors, such as SharePoint and SQL. From the overview page you can also get to the general Connector reference that covers the 300+ standard and premium data connectors for Power Apps, Power Automate, and Logic Apps. You can also view a filtered list of connectors that work with Power Apps. For Power Apps, the important things to know about each connector are the various definitions, and any limitations such as throttling or delegation.
There is some in-context documentation when creating a canvas app in the Power Apps designer. To learn about available functions, click on the fx button, select a function from the dropdown, and click Learn more… This will take you to the Formula Reference area of the Power Apps documentation, which is a comprehensive list of all functions. For each function, you’ll learn its syntax, parameters, and outputs, and some examples are shown.
Another important reference area is the one for Controls, which are the elements that can be placed on the Power Apps canvas. This reference lists and describes each control, and all the properties related to each one.
Great site with super resources.