Do not try to play 4K videos. Stick to 720p or 1080p. Also, avoid using YouTube Live Streaming on Lollipop—the chat feature will cause the app to hang.
While Google has abandoned Lollipop, the community has not. The search for reflects a global need to keep functional hardware alive. The definitive answer is YouTube 17.09.38 —a version that offers the best balance of modern UI, stable playback, and low resource consumption. youtube for android 511 top
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