I have read everywhere that in 15.4 you can use your iPhone or iPad to do the name/room number aspect of joining a hotel network. But nothing online at the moment says exactly how it works, step by step. The only intel I found was the article below which was sorta vague... to me...
I have used my ATV(s) since they was first released all over the world in hotels by providing to them the MAC address of my ATV(s). Most of the time, I can do this prior to my hotel arrival. These days most can do it in-house but sometimes they have to call their ISP's to manually add my ATV address to their system. I have taught many hotels how to do this....LOL
The new feature contained in 15.4 will make life quite a bit easier... I was in a hotel just two week prior to the release of 15.4 and had my MAC address added to the system... A few days difference and I would have used the new way....
BTW, the cheapest Firestick (which I dislike) has had this feature for many years; Apple's method requires a iPhone or iPad...
www.macworld.com
I have used my ATV(s) since they was first released all over the world in hotels by providing to them the MAC address of my ATV(s). Most of the time, I can do this prior to my hotel arrival. These days most can do it in-house but sometimes they have to call their ISP's to manually add my ATV address to their system. I have taught many hotels how to do this....LOL
The new feature contained in 15.4 will make life quite a bit easier... I was in a hotel just two week prior to the release of 15.4 and had my MAC address added to the system... A few days difference and I would have used the new way....
BTW, the cheapest Firestick (which I dislike) has had this feature for many years; Apple's method requires a iPhone or iPad...

tvOS 15.4 lets you finally log in to captive Wi-Fi portals on Apple TV
tvOS 15.4's Captive Wi-Fi feature lets you use your iPhone or iPad to sign into pesky Wi-Fi portals.
