There’s a new video of the Nordic Semiconductor webinar on Everything you need to know about Bluetooth LE advertising. It covers the basics of Bluetooth LE including advertising and data formats. It explains how to use the nRF Connect SDK API and provides a demo. It also shows how to use nRF Sniffer to examine Bluetooth LE data packets.
The presentation and Q&A are also available.
The video mentions advertising extensions. These are only in Bluetooth 5. Most current devices only support Bluetooth 4.2 legacy advertising. Growth in numbers Bluetooth 5 devices has been limited due to the non-compatibility with the majority of smartphones. It’s for this reason that devices that are Bluetooth 5 usually communicate using, backward compatible, legacy advertising. Extended advertising is also an optional feature of Bluetooth 5.