If you have an iPhone, you probably noticed that the default search engine on it is Google. It doesn’t matter if it’s an older iPhone, or one of the recently announced ones. There’s a price Google is paying for this privilege. Past reports have briefly touched on the idea of some sort of arrangement between the two companies, but there was no mention of a specific amount.

Google and Apple are both silent about this, but analysts are trying to estimate the numbers. The general consensus was that we’re looking at billions. A recent Business Insider report cites analyst Rod Hall, who believes Google pays Apple $9 billion to remain the default search engine on iPhones.

Apple and Google are competing in the mobile space bot in hardware and software. Needless to say, their relationship isn’t an ideal one, but apparently, Google considers this money well spent. While the number of Android devices in the world is much higher than iPhones, the Apple smartphone is still taking up a huge chunk of the market. In order for Google to capture that, the report claims that the amount could go as high as $12 billion starting 2019.