Strange suspicious results from google admob ecpm

Something very strange has happened to me on admob with my game on android. For months my 1st game TorpedoRun on IOS was getting an admob ecpm of around 40-80c maximum which I thought was pretty rubbish. Then I released an Android version of the same game and for weeks I was getting around $7.00 ecpm for the android version but still a rubbish 80c for the IOS version.

I concluded that Google must be biasing ecpm to Android games on admob to encourage developers to put their games on that platform. SO like an idiot I published my second IOS game onto Android thinking I’d get another game hitting $7.00 ecpm.

Within a day of publishing the second android game the ecpm on the 1st one plummets down to 70c, and the new second game also gets a paltry 70c. What happened? How did publishing a second game kill the ecpm on the first?

Anyone else had a similar experience?

I guess not.