We can confirm an issue with the Zattoo app with tvOS 11 beta. The app crashes when you go to Channels. We are now investigating this problem and will solve it before the the tvOS release in autumn 2017.
In the meantime please downgrade the tvOS version if you want to use the app without any issues.
How to downgrade tvOS 11 Beta to tvOS 10
1. Connect your Apple TV 4 with your PC or Mac using a USB-C to USB-C cable or a USB-C to USB-A cable.
2. Once connected, make sure you download and install iTunes and launch it.
3. Select your Apple TV 4 from the top left hand side of iTunes.
4. You will see a bunch of information pertaining to your Apple TV, but click on the Restore Apple TV button while holding down the left Option key (Mac) or the left Shift key (Windows).
5. As a new pop-up window shows up, just select the tvOS 10 firmware file you downloaded at the start of this tutorial.
6. iTunes will now unzip the content of the firmware file, verify it will Apple and ultimately restore your device.
The entire process will take no more than a few minutes and iTunes will immediately throw you a notification when everything is complete. Once that happens, just unplug your Apple TV 4 from your computer and plug it back to your TV. Sign in using your Apple ID and use as your normally would.