All you need to do to cast the app is to:

1. Make sure your Apple TV or AirPlay 2-compatible smart TV and iOS device are connected to the same Wi-Fi network.
2. Open Control Center:
   On iPhone X or later or iPad with iOS 12 or later: Swipe down from the upper-right corner of the screen.
   On iPhone 8 or earlier or iOS 11 or earlier: Swipe up from the bottom edge of any screen. 
   
3. Tap Screen Mirroring.
   
4. Select the device you want to mirror to.
5. If asked for a password, please enter the one that appears on the TV screen.
6. Open Tabs and enjoy the big screen experience!   
   



For a more detailed explanation, please visit: https://support.apple.com/en-us/HT204289#mirroriOS

If you haven't yet connected your iOS device to a TV yet, please refer to this instruction: https://support.apple.com/en-us/HT208724