What is an app list in Skie and how is it different from a policy?
An app list is the set of apps a group may use. A policy holds the rules and settings. Skie keeps them apart, so you can change which apps students see without touching hardening, and the other way round. A group has one of each, and an app on no list is hidden or removed from the device.
An app list names the apps that are allowed on a group's devices. Everything else that you did not allow is hidden or suspended, and an app installed after setup that is not on the list is removed silently by the install guard. Apps are hidden or suspended rather than deleted, so their data returns if you allow them again.
A policy is different. It holds the switches: factory reset blocked, safe mode blocked, Chrome rules, filter choice, camera, Bluetooth and the rest. Keeping the two separate means a school can run one standard policy and several app lists, one per grade, instead of duplicating every switch for each.
Lists have a few extra behaviours. Essential system apps are never touched, so the device stays usable. Some apps are always blocked, such as VPN apps, proxy apps and over fifty alternative browsers, whatever the list says. On a device model that has not been reviewed, built-in apps are left alone.
A practical tip: build lists by purpose, for example 'Junior learning apps' and 'Staff work apps', and reuse them through the app list library. Pair a list with a schedule when the allowed apps should change during the day, such as a narrower set in a study block and a wider one at break.