You finish a hike and you want to look up where to get a snack, but your smartphone can’t find service. Your car garage is a dead zone. Or maybe you’re traveling internationally and don’t want to pay for smartphone connectivity. On Tuesday Google announced a new feature for its popular Maps service that will allow you to store data offline so you can look up local businesses and start turn-by-turn navigation when your device is totally cut off. And if service comes back at some point, everything seamlessly updates with the real-time data you’ve been missing.
The idea is that you select a broad geographic area that encompasses all the regions you might go to on a typical day. Google Maps calculates how much storage it will take to keep the information for that area locally on your device, and then you start the download. Amanda Bishop, a product manager on Google Maps, says that the Bay Area weighs in at about 200 MB, New York City is around 250 MB, and London is around 300 MB. (To compare, the Google Maps app by itself takes up 36.1 MB on iOS.) In offline mode, you won’t see photos or written user reviews for local businesses and you can’t get traffic estimates, but there is still information like hours of operation and phone numbers for businesses, and routes update and adapt to traffic conditions if your phone regains service.
“This is not just a map, this is the full-blown thing,” Bishop said. “The biggest engineering challenge is that Google Maps was architected from the beginning to be a cloud-based app that leverages the power of Google’s cloud and all of those servers and those massive cores that can crunch on these really complex algorithms.” She explained that condensing the Google Maps product into something that could be powered by a typical smartphone processor was difficult. “But we really did want to do that, we didn’t want to build something for offline from scratch because then you can’t do this seamless transition between the two.”
If you travel all the time for work or are going on a long vacation, you can even download an enormous area, like all of Europe, if you have the space to store the data on your phone. But even if you have a low-end smartphone that doesn’t have a very powerful processor, offline maps is designed to work. Google sees one of the feature’s most crucial use cases as being in emerging markets. “Mobile data speeds are really slow, 2G primarily, 3G at best,” Bishop said. “And [data] is also really expensive relative to those users’ incomes.” Being able to store a region’s data on a device through a one-time download (that updates when a device has connectivity) means an initial investment to do the download followed by the option of using zero data for mapping in the future.
It’s going to be easy to get used to this. The hard part will be forgetting to do the big downloads for new places and just expecting it to work everywhere.