On your Android TV or Box, go to: Toggle this setting to ON . This allows you to install apps from sources other than the official store.
For , the original "Smart YouTube TV" app and its successor, SmartTube (formerly SmartTubeNext), are specifically designed to work on older operating systems starting from Android 4.3 and above . Recommended Version for Android 4.4.3 smart youtube tv apk android 4.4.3 free download
: The app functions independently of Google Play Services, which is often broken or unsupported on Android 4.4 devices. On your Android TV or Box, go to: Toggle this setting to ON