yuliskov/SmartTube: Browse media content with your ... - GitHub
The correct is stripped-down but feature-rich considering its age:
: SmartTube is an open-source YouTube client designed for TV interfaces that allows for ad-free browsing and playback. Key Features No Ads & SponsorBlock
Given that Android 4.4 (KitKat) is a very old operating system (released in 2013) with severe limitations on RAM, processing power, and codecs, the best "interesting feature" is one that solves the hardware bottleneck.
The Little Phone That Could