Apple has told developers to stop developing location-based service apps for its App Store. The company is likely to want to stitch that market up for itself.
Google is probably the world's biggest advertising company. And Apple won't be handing over lucrative avenues now that the pair are direct competitors in so many markets.
On its Developer Connection blog, Apple proclaimed: "If your app uses location-based information primarily to enable mobile advertisers to deliver targeted ads based on a user's location, your app will be returned to you by the App Store Review Team for modification before it can be posted to the App Store".
Location-finding applications must give iPhone users "beneficial information", such as weather forecasts or information about restaurants or traffic. Ads for other services are disallowed.
Apple is thought to be working on its own ad-delivery system for its growing mobile platform.
Over three billion apps have been downloaded from the App Store, and most are initially free. And with books and music and gaming blended in the mix, Apple will be looking to best exploit the hearts and minds of its growing audience through a smart advertising model.