The Federal Trade Commission announced that Google agreed to the settlement to resolve a probe into unfair practises by billing consumers for charges by children made within kids' apps since 2011.
FTC chairwoman Edith Ramirez said in a statement that in the age of mobile technology, "it's vital to remind companies that time-tested consumer protections still apply, including that consumers should not be charged for purchases they did not authorise."
The in-app charges are a component of many apps available from Google Play and can range from 99 cents to USD 200, according to the consumer regulatory agency.
In some apps used by children, users are invited to accumulate virtual items but sometimes are billed without the knowledge of their parents.
Google has also agreed to update its practices to ensure that it receives parental consent for the purchases.
The agreement follows a similar deal earlier this year with Apple, which agreed to pay USD 32.5 million.
The FTC in July sued Amazon as part of its investigation into in-app purchases by children, but no settlement has been announced.