The big picture: Fast Pair is a more open alternative to Apple's W1 chip used in AirPods that allows for a fluid experience without dealing with an inconvenient pairing process every time there is a desire to connect Bluetooth earbuds to a different device.
A lack of headphone jacks on smartphones has pushed many towards the use of wireless headphones and earbuds. Unfortunately most good Bluetooth headphones or quality wireless earbuds are still fairly expensive and the process of pairing them to multiple devices can be clunky.
Google is making an update to its Fast Pair feature present on Android and Chromebooks that will allow pairing information to be synced to the cloud. Once you pair a device, the connection will be stored to your Google account and recognized by all other devices linked. If you pair headphones with your phone, they can then be automatically connected to any other device signed in with a Google account without going through the pairing process again.
Fast pairing support is not yet prevalent in many Bluetooth accessories, but that is going to change over the next few months. Jaybird's Tarah earbuds are the only product that Google has specifically recognized as having Fast Pair support. However, there is confirmation that Bose and Anker SoundCore will be adding Fast Pair to some of their products. Perhaps CES 2019 will reveal some new options.
Bringing Fast Pair to as many Bluetooth audio devices as possible is something that Google seems genuinely interested in. Collaboration with Qualcomm, Airoha Technology Corp, and BES Technic will ensure that Fast Pair is part of software development kits that are frequently used.
Starting today, supported devices on Android 6.0 and above will begin to take advantage of one time pairing. Chromebooks will be receiving an update in 2019 to add the updated feature.