Youtube Watch hours is the total amount of time in aggregate that viewers spend in watching your videos.
For a publisher to qualify to join the youtube partner program (YPP), he must have a minimum of thousand (1,000) subscribers and four thousand (4,000) watch hours.
ALSO CHECK: How To Get More Subscribers And Views For Your YouTube Channel
Here is the process involved in checking how many watch hours / watchtime one has accumulated on phone.
1. Download youtube studio on Google play store or apple store.
2. Login your youtube channel (Email and password).
3. Click on the menu on the top left corner.
4. Select analytics
5. In the page displayed select watchtime (hours).
6. Click on the drop down arrow on top of the watchtime, and select lifetime to display the overall watchtime.
ALSO CHECK: How to apply for youtube monetization (Video tutorials)

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