If you use SmartTube, you need to uninstall it and install this new version due to a security issue

If you use SmartTube, a popular YouTube app for Fire TV and Android/Google TV devices, it’s important that you uninstall the version you’re currently using and install the new version that was just released. This is because the app’s developer has announced that the app’s digital signature has been exposed, which means all updates to the old version of the app can no longer be trusted.