Many iPhone owners had held off upgrading when Apple's own map app, which replaced Google Maps found in previous versions of iOS, proved flawed and inaccurate.
Mobile ads network MoPub said it has recorded a 29 percent increase in iOS 6 users since the release of Google Maps for iOS, Computerworld reported Wednesday.
"It verifies the hypothesis that people were actually holding back to upgrade until Google Maps was available," MoPub's report said.
Google reported more than 10 million installations of Google Maps for iOS within 48 hours of launch.
Apple is reportedly working rapidly to improve its own map app in iOS, and there have been rumors it is looking at acquiring mapping data provider TomTom.