Android marketplace app free-to-paid conversion rate
I have two games on the Android marketplace that have a free/lite version, and a paid version. In both cases the # of sales divided by the # of free version downloads is approximately 3.1%. 

My questions are these:

 - Is that a good %? If not, what is a typical good value to have there?
 - Is there a different measurement that I should be looking at rather than this purchases-to-downloads ratio?

Thank you
Android marketplace app free-to-paid conversion rate
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I have two games on the Android marketplace that have a free/lite version, and a paid version. In both cases the # of sales divided by the # of free version downloads is approximately 3.1%. 

My questions are these:

 - Is that a good %? If not, what is a typical good value to have there?
 - Is there a different measurement that I should be looking at rather than this purchases-to-downloads ratio?

Thank you