It's probably no coincidence that Google is the default search engine on iOS devices.

The Internet search giant shelled out $1 billion in 2014 to keep its dominant place as a search option on Apple's mobile products, according to a recent report by Bloomberg.

Apple did not immediately return CNBC's request for comment. Google declined to comment on the report.

The sum was revealed in a court transcript of proceedings from Oracle's ongoing federal copyright lawsuit against Google. An attorney for Oracle reportedly revealed the deal during a Jan. 14 hearing. Oracle also declined to comment to CNBC.

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The agreement gives Apple a percentage of revenue Google generates through searches on iOS devices, according to the report. Google's lawyers had asked the judge the strike mention of the revenue-sharing agreement from the record, but the judge refused to seal the information.

"The specific financial terms of Google's agreement with Apple are highly sensitive to both Google and Apple," Google said in a Jan. 20 filing, according to the report. "Both Apple and Google have always treated this information as extremely confidential."

Read the full report here.