Hello,
Is your Amazon account in Switzerland or somewhere else?
Sometimes it helps to use a VPN on your Amazon network to install apps from your base account
As a replacement for the Google Chromecast, I recommend a new one with 4K and Google TV, so that Google services such as Google Home and YouTube can be used more optimally. Alexa products do not have a Google Play Store.
Google Chromecast with Google TV 4K (Google Assistant)
It also supports Dolby Vision and Dolby Atmos.
The only difference seems to be in the delivery content:
Item: 17257486 includes:
- Fire TV Stick 4K Max
- Alexa voice remote control (3rd generation)
- USB cable and power adapter
- HDMI extension cable for Fire TV Stick 4K Max
- 2 AAA batteries
- Quick start guide
Item 17257487 includes:
- Fire TV Stick 4K 2021
- USB cable and power adapter
- HDMI extension cable
- 2 AAA batteries
- Quick start guide
This is not a function directly supported by the Fire Stick, because the Amazon devices cannot simply be used with programmes from the Google Play Store environment. This is not possible.
But it would be much better to use this Android TV player anyway, which can also do 4K and offers a very good remote control with which you can also control TV devices, doesn't cost much and can then use the Swisscom app from the Google Play Store:
Google Chromecast with Google TV 4K (Google Assistant)
It can also do DolbyVision and Dolby Atmos as well as HDR10+,
Netflix & Disney+ run on it. Unfortunately, there is no app for HBOmax. I think I read somewhere that you can watch it on the browser via detours. I can't answer that for sure because I'm not an HBOmax user and live in Germany.
This is what the Sunrise website says:
You can access the following functions abroad:
ComeBack TV (shortly after the broadcast)
ComeBack TV Agent
Recordings
TV Guide
For legal reasons, this function is not available:
live TV
Cost control abroad
Roaming is deactivated for the Sunrise TV streaming application to avoid high data roaming charges.
As far as Amazon is concerned, here is what the Sunrise website says:
Choose the Appstore via the main menu.
Search for the Sunrise TV application using your voice.
Select the Sunrise TV application.
Click on "Download" to start the download.
You can also go directly to the Amazon website:
Search for the Sunrise TV app.
Install it directly on your Fire TV by clicking on "Deliver".
Tip: For the installation on the Amazon website, you need to be logged in with the same Amazon user data as for your Fire TV account.
You can find more help in the Amazon Fire TV forum.
I did a quick search for "neXtv" on my Fire TV Stick in the App Store and found nothing.
It doesn't seem to be available.
You can also search for available apps yourself:
https://www.amazon.com/Fire-TV-Apps-All-Models/b?ie=UTF8&node=10208590011