How much better is GPS over Wi-Fi positioning? Yelp knows

When you have millions of location data points, figuring out how much more accurate GPS is compared to Wi-Fi is a snap. Luckily, Yelp just happens to have that type of data, captured through users of its app who check-in at various business locations.

Earlier this week, the company scoured the data and shared the results in a blog post. It turns out GPS is twice as accurate than Wi-Fi for very fine data and, possibly due to low-end devices with inexpensive GPS chips, Android devices as a whole are less accurate than iPhones.

Yelp took a deep dive into the geolocation data from June and ended up with a nice chart showing the difference in accuracy from check-ins on the iPhone, Android devices and the iPod touch, which has no GPS and therefore relies on Wi-Fi-based location data.

As expected, the GPS devices are far more accurate than a Wi-Fi only device. Nearly 60 percent of all Yelp check-ins were within 0.1 miles of the actual location on iPhones in June, while just 30 percent of iPod touch check-ins were as accurate. Surprisingly, the Android devices were closer in accuracy to an iPod touch, even though nearly all Android devices have GPS chips.

If you can live with some tolerance for location data, Wi-Fi isn’t terrible: Yelp’s data shows that 79 percent of all iPod touch check-ins were within a mile of the business location.

That doesn’t sound like it’s good enough to ever displace GPS when out and about, but Wi-Fi certainly works better for indoor location needs such as in a mall, large retail store or educational facilities. As a result, both types of geolocation methods are likely to be used in a hybrid form for some time to come.



GigaOM