I'm amazed that this equation managed to calculate that 25 billion downloads on the Play store would be on the 25.3th day of the month, which is today! :D Math level=Asian.

If you want to try the equation:
- Downloads predicted at the start of September: https://www.google.com/search?q=(8.6*47)%5E3.977278527082
- Downloads predicted at the start of October: https://www.google.com/search?q=(8.6*48)%5E3.977278527082

Play announcement:


The Maths

Prediction for downloads at beginning of Sept: 23.28bil
Prediction for downloads at beginning of Oct: 25.32bil

Difference between 2 months=2.04bil


I know it's not a linear increase, but it's close enough.
Analysis of the downloads on the Android Market. Any statistical analysis has error, but this should be no more than 10% in mine.

Cumulative Total Download increase is:

Increase of downloads of a certain month is:

My predictions for the Android Market by the end of 2011:
Total Downloads: 11.09 Billion
Downloads in Dec 2011: 1.09 Billion

This should give a reasonable estimate:
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