How can I keep apps from moving off the home screen?
A work-around you could use on Android to refrain from having apps move or be uninstalled by either accident or someone trying to purposely do so:

Settings -> Accessibility -> Dexterity and Interaction -> Press and hold delay -> Custom

From here, you can just set an obnoxiously long press and hold delay so that when icons are held down to be either moved or uninstalled, it takes however long you've set the interval for to actually initiate that command. So, a) doing it by accident becomes harder and b) Someone who doesn't know you've set that feature will assume it doesn't work and not opt to wait 35 seconds of holding an icon down.

Just my little trick, at least.