Android Google Map key for professional use?

Is there any limit on number of hits per day/hour on free Google Map Key for Android? If yes then what is the process to purchase a key? I did not find any link on Google's web开发者_StackOverflow社区site.

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I think there is no limit for the number of queries on Google Map API. Go in your Google API console and you can see the hit-limited APIs.

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Use the service till you can. You will know the result in the end.

Google will automatically let you know when to pay, and how.