Herald was originally created to solve the problem of very variable and unreliable Bluetooth mechanisms on Android and iOS devices. Over 40 techniques and workarounds are present in how Herald works.
As it turns out these same problems are also applicable for a wide range of other applications.
Herald supports over 98% of phones worldwide - this includes phones that do not support advertising their presence themselves. Many contact tracing protocols in use today fail to take this scenario in to account, meaning they miss around 35% of all Android phone users.
Reliability of the Bluetooth stacks within Android and iOS is also very questionable, requiring exact protocol use and testing to workaround. This takes application developers away from solving medical and epidemiological problems. By using Herald, these teams can again concentrate on their residents and patients and leave the reliable Bluetooth messaging and range finding to Herald.
Please see the Contact tracing introduction for a discussion of the many issues with manual and mobile contact tracing.
By adopting the Herald envelope for your contact tracing app (supported by all our suggested payloads) you will ensure that wherever your country’s residents travel to, their application can be used as-is internationally. We recommend the Secured payload in this instance.
Using the new Herald Beacon Payload a phone supporting the detection of Herald Beacons (but using ANY contact tracing protocol) can build up a diary of check-ins and check-outs from venues.
This means people don’t have to remember to scan QR codes for locations which is error prone. Multiple beacons can be placed in big venues, hospitals, or company campusses with specific area names to provide more fine-grained exposure notifications.
Herald Beacons also track the full time from check-in to check-out to minimise false exposure notifications to wrong people who happened to turn up on the same day, but at different times and areas within a venue, to people who were ill.
For younger school children without phones, or for the elderly too, a contact tracing solution is needed. A cheap Bluetooth enabled wearable is a good solution here. This may or may not be backed up by a local Bluetooth mesh network to reduce the cost of the end device.
We are implementing Herald in C++ for Windows and Embedded use cases. Our first target platform will be Nordic Semiconductor nRF52840 usb dongles for our reference implementation. This uses the Zephyr open source real time operating system (RTOS). This is currently in Alpha development.