I have a question about an analysis with the ScroolDownPercent method or getPercentPageViewed, how can I make a meaningful analysis here?
There are always different devices with a different display size e.g.: My laptop screen has a larger size than my iPhone, this also tells us Google Chrome with the tool "Examine" > Console > Search "prop32". iPhone 5: Has a prop32 value of 16 iPhone X: Has a prop32 value of 23 My Screen: Has a prop32 value of 23 * These values are the initial value when coming directly to the same page, only with different emulator devices.
Does anyone here have a useful solution how to analyze these values meaningfully? The problem is namely with me that yes every screen, smartphone has a different starting point.
As you've discovered, the percentage scrolled depends on the screen height. Recall basic maths: percentage = numerator / denominator x 100%. In this case, the denominator is the screen height. So when the denominator changes, the percentage changes too. And that's what you're experiencing with the various scrolled percentages.
A better analysis would be based on element visibility. Regardless of screen heights and browsers, users will want to read the part(s) of your page that is interesting. So track when certain elements in your page have become visible in the browsers' viewports (maybe after a delay, to account for users scrolling through the page quickly).
If you know that element A comes before element Z in the page, yet find out that element Z gets more views than element A, then you know something interesting is going on with how your users are reading your page's content.