I've seen on the iPhone version of Coin Dozer, it is possible to change the 4 stars into 5 stars (meaning you can use coins quicker).
Is this possible on Android? And if so how do I unlock it?
It is possible on Android. These screenshots were taken this morning from my S3.
When below 50 coins, only 4 stars are available:
But when you have 50 or more coins, 5 stars are available:
It may have been added in a recent update, but the Android version certainly can have 5 stars.
I think you can safely say the answer is no. There is no information on the internet to support an increase in stars at any level.
From personal experience, I have played the game to a near 100 level and have had thousands of coins and the number of coins available to drop at one time has not changed.
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