How can I mirror my Android to my TV without an app?
Restart your phone and TV, and then try mirroring again. Update your devices' software. If you're using an older version of the software on your phone or TV, there may be a bug that's causing the mirroring to fail. Updating the software may fix the problem.
What do I need to mirror my Android to my TV?
If you don't have a smart TV or chromecast, but your TV has an available HDMI input, you may be able to connect your Android phone using an HDMI adapter - you need to check your phone's specs to see if it would be compatible with this connection option.