Product design question

How would you improve battery life on YouTube mobile without making changes to the UI/UX?

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What this question tests

Technical product thinking under an explicit constraint, checking whether you can find non-UI levers like backend and encoding efficiency to solve a hardware problem.

How to approach it

  1. Clarify the constraint: no UI or UX changes allowed, so the fix must live in backend processing, encoding, or system-level resource usage.
  2. Identify the biggest battery drains for mobile video: continuous decoding of high-bitrate video, background processes, and network radio usage during buffering.
  3. Prioritize adaptive bitrate and codec efficiency, since more efficient video decoding directly reduces CPU and GPU load, the largest battery consumer during playback.
  4. Propose a fix: expand use of a more power-efficient codec like AV1 where device hardware decoding support exists, reducing decode-related power draw without any visible change.
  5. Address background behavior: reduce unnecessary background buffering or preloading of unwatched recommended videos when the app is not in active focus.
  6. Define success as measured battery consumption per minute of playback across device types, tracked before and after the change.

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