Measure precipitation rate

It’d be helpful if the help article mentioned that precipitation rate can be measured & how to measure it: How To Calculate Precipitation Rate | Sprinkler School

Even better it’d be great if the app could help a user with that short run with a bucket + calculation depending how long it ran. I understand the app currently let’s you calculate your rate but you must know your number of SQ ft + gpm + number of sprinklers. More often than not one does not know those. Additionally measurement is always more accurate than manufacture spec.