I plan to mount an iPad as a display in my KNX setup with Home Assistant.
But what do I need to place in the wall behind the wall mount?
POE.
Emonita and iport both have very nice wall mounts.
No need for PoE.
An iPad have no ethernet connection.
You need a way to get power to it and you might be able to find angled connectors, so it can be hidden inside the wall mount, but you need to check with the wall mount first to see what is possible.
Disagree.
POE is the best way to get power to a wall mounted tablet.
Maybe if you have a POE enabled switch somewhere, you have a star shaped cabling and you live in some country where cable conducts in wall permits the passage of huge cables.
Otherwise a couple of smaller L+N cables from the nearer socket and a small power supply hidden in the socket receptacle or, worst case, a flat line cable running along the wall….
It is fine that you want to pull a PoE cable to the iPad, but you need a transformer to be able to plug it into the iPad, so you will have another plastic box to mess with and the ethernet network can not be used with the iPad anyway.
Disagree. PoE only makes sense for high-bandwidth devices like cameras and access points. PoE is overrated, overpriced, and overkill for anything else.
Globally, usb-c (with PD3.0) is the modern connector of choice for low-voltage (5-20v) use. It is easy to find in dc power supplies, ganged with AC outlets, and now pd3.0 voltage step-up adapters. It would be trivial to install any of these in the wall for a tablet.
Furthermore, WiFi 6 is also far superior to previous versions, so if you have a bad impression of WiFi due to old and subpar ISP routers, you should strongly consider upgrading. And iPads have both of these (usb-c and wifi 6) built in! Why make it harder on yourself?
I am in the US. POE is low voltage and the easiest thing to route through walls and make it look nice.
Now once it gets there it changes over to USB-C.
I was only vouching for POE for power. WiFi is not germane to this discussion.