The app drawer lists all installed apps, in a scrolling list (vertically by default, but it can be set to horizontal too).
The app drawer can be configured roughly the same way as a desktop and shares almost all styling option with a normal desktop, but works a bit differently since it has some specific features.
In LL, swipe left/right will toggle between “show only hidden apps”, “show all apps”, “show only visible apps” modes. In LLX swipe left/right will switch between the different views My Drawer, Alphabetical, Recently launched, Recently updated, Used often, Currently running.
Pinch zooming will change the number of icons displayed on the screen, not the scale of the view (except in the custom “My Drawer” view in LLX).
The app drawer supports almost all styling options from a desktop. The Lightning Launcher eXtreme app drawer also has a custom view where you can move icons, create folders, change appearance, etc.. In order to set a custom layout and organize apps in folders, switch to the “My drawer” view first.
The advanced app drawer search app function is available through the magnifier icon at the top of the screen, but the search can also be called from a desktop through a shortcut “LL action / search app”.
It might be the app drawer is out of sync with the Android list of apps, this can happen for instance after a device firmware update. In the app drawer, use the “Refresh” menu to update the app drawer.
Long tap on the desktop (or folder or panel), select “Add” then “App”. Without leaving the App Drawer, repeatedly long tap on a app and select “Add to launcher”.