We look at the deceptively-named "LeaveHomeSafe" app, and why it failed to adopt the automated technology worked out by Google and Apple for exposure notifications and instead resorted to a home-brewed QR-scanning system that few will use. The answer may lie in politics.

The geo-politics of HK's clunky contact-tracing app
19 November 2020

There are so many things wrong with the HK Government's COVID contact-tracing app that it's hard to know where to begin.

Let's start with the name, which is grossly misleading. It's called "LeaveHomeSafe" (LHS), but it does nothing to make it safer to leave home, of course. You have the same risk of contracting the virus whether or not you are using the app. The cheery video that accompanied the launch carries the voiceover: "Use the app together. Feel at ease when going out." This is contradictory to the ongoing Government advice to "avoid eating out or going out if it's not necessary" from that patronising and irritatingly childish "Lazy Lion" character.

Secondly, the Government has completely ignored the system now built in to Apple's iOS and Google's Android software known as "Google/Apple Exposure Notifications" (GAEN). This simple system works by automatically exchanging anonymous randomized tokens with phones nearby using Bluetooth Low Energy (BLE). The tokens change every 10-20 minutes. No location information or personal data is recorded or needed. You don't need to keep any app running in the background, because it works at the operating system level. All you have to do is turn it on. If someone tests positive, then a notification is sent to all devices with matching tokens using a code provided by the local health authority, telling other users that their device has been near someone who tested positive, but without saying who or where.

Some US states such as Colorado have even gone without the need to install an app on top of the operating system. This is known as Exposure Notifications Express.

By contrast, LHS requires the user to install an app and scan QR codes whenever they arrive at somewhere that displays one, and remember to tap "Leave" when they leave. Who's going to remember to do that after a few drinks? The same manual check-in-check-out procedure applies to taking a taxi ride or a bus (if the buses get around to it). Will you remember to do that while carrying your bags? How many locations will bother to generate a QR code? It's all too much hassle for users and will be poorly adopted.

Thirdly, by recording a location history of QR codes and matching those up, it limits the scope of the contact-tracing, because there are some places that people don't want to record themselves as having been. Also, some places are just too large - a hotel, for example, for a QR code at the entrance to be meaningful. The BLE system records signal strength and only those within a short range, making it much better suited to narrowing down the target list for contact alerts.

The possible motivation

So, what's the motivation for the HK Government reinventing the wheel and coming up with something less than circular? It may well relate to the "not invented here" problem that both Google and Apple are US companies while HK is an inalienable part of China (as we are constantly reminded), and China these days seeks to avoid using foreign technology. It may also be because Chinese vendor Huawei is currently banned from using Android updates in its new phones after May-2019. Hence LHS comes in 3 versions, for Apple, Google and Huawei.

However, Huawei has produced its own version of exposure notifications known as HMS Core Contact Shield (HCCS), which also uses BLE. According to the Huawei FAQs:

"The Bluetooth technical specifications of Contact Shield are consistent with those of the GAEN. Therefore, Contact Shield can properly interwork with Google and Apple devices."

So it should not be beyond the abilities of a competent developer to create an app that uses both GAEN and HCCS, if HK is the hub of innovation that it claims to be. Even if that integration is not yet possible, Huawei phones only account for about 11% of the HK market, so is that a good reason to drop the benefits of GAEN for everyone else? Lives may be saved by promptly notifying close contacts before they can become symptomatic and spread the virus to others.

We don't know who specified the design of LHS, how much it cost, or whether the project was tendered, but the Google Play Store shows the developer email as "info@cherrypicks.com". That domain belongs to Cherrypicks Limited (Cherrypicks), which is now 92.2% owned by Fujian-based game developer NetDragon Websoft Holdings Ltd (0777). The Founder and CEO of Cherrypicks, Jason Chiu, is a Government-appointed Councillor of the Hong Kong Trade Development Council and the University of Hong Kong.

© Webb-site.com, 2020


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