When a canvas app adds a SharePoint list from Recent sites, it remembers that site's address. To have it follow environment variables instead, so a new environment only needs new values, add the lists through the Advanced tabs. They take a few more clicks, and they're easy to miss.
The Office 365 Users connector gives a canvas app people's Microsoft 365 profiles: name, email, job title, department, manager and direct reports. It's a standard connector, so it comes with Microsoft 365 licenses that include Power Apps. Adding it takes a minute from Studio's Data pane.
A new canvas app starts with App layout set to Fixed: Power Apps zooms the whole screen to fit the device, so a tablet-shaped app on a phone becomes a thin strip. Switch it to Responsive and each screen takes the size of the window instead. It's one setting, and it's the first step to an app that works on phones, tablets and desktops.
A canvas app's description is a sentence or two about what the app is for. Power Apps Studio keeps it in the app's Settings, and its own hint says why: "Provide a description to help end-users find and use your app." Here's where to type it and where it shows up afterwards.
An environment variable can point at a SharePoint document library as well as at a list. There's no separate Library type: you choose List, and the site's libraries are offered alongside its lists. Here's the whole thing, using a payroll library as the example.
Overtime is pay, and pay is private. This part makes SharePoint itself enforce that, not just the app: each person can open only their own overtime entries, nobody but the site's owners can delete them, editing an approved entry sends it back for approval, and payroll's library is for payroll alone. Then four people sign in and try it.
A document library starts out open to everyone who can open its site. To keep one, say a payroll library, for a single group, give it its own permissions: stop inheriting, remove the site's groups, and grant the one group that should have it. People outside the group then get You need access if they try the library's address.
Once a few lists stop inheriting their site's permissions, it gets hard to remember which ones. The site's Permissions page keeps track for you: a Show these items link opens an Exceptions dialog listing every list and library with its own permissions, each with a link to manage them.
Every time someone saves a change to a SharePoint list item, the list can keep a version of it. Version history shows them all: the version number, when it was saved, who saved it and which columns changed. It's the item's audit trail, and it's two clicks away.
"Why can she see this?" and "why can't he open that?" have the same answer in SharePoint: Check Permissions. On any Permissions page, it shows the permission levels one person has on that site, list or library, and the group each one comes through.
