What is the Physical Web
The Physical Web allows users to discover URLs based on their surroundings. For example, you might see a movie poster and wonder when the next showing is. You could open your phone and search for the movie or download an app to find the listings, but there is a much easier way. That movie poster could have a Bluetooth beacon in it that would automatically alert your phone with the URL for updated show times.
Other examples would be a parking meter providing you with the appropriate link to pay through the cloud or for finding out when the next bus is going to come by.
What are beacons?
Beacons are small transmitters that can send information via Bluetooth LE. They typically transmit information every second whether or not other smartphones are nearby.
Google has its own open-source cross-platform technology called Eddystone, while Apple utilizes its own iBeacon technology. Both work the same way, but the advantage to Eddystone is that it works with both iOS and Android. Apple’s iBeacon only works with iOS devices.
How it works
Assuming you have Chrome for Android, when you walk by a beacon for the first time, you’ll receive a notification asking you to enable the Physical Web. Once enabled, you’ll receive non-vibrating notifications every time you’re near a beacon. These notifications will consist of related URLs that you can open in Chrome. Your phone must be out of your pocket and awake for it to scan for beacons and receive notifications.
Chrome users on iOS already have this same ability via the Today widget, which shows an on-demand list of web content relevant to their surroundings. Google launched support for the Physical Web in Chrome for iOS last July.
It should be noted that whether you’re using an iPhone or an Android device, Chrome for Android will only recognize beacons using the Eddystone standard. Apple already has its own Core Location APIs that are compatible with iBeacon and work with iOS. There are a number of apps already available in the App Store.
The Physical Web will be available in the beta version of Chrome for Android starting with version 49. Google did say that it will become more widely available soon.