Japanese contact tracing software of Covid-19 patient on Android did not work for four months

The following item explains it all.

https://english.kyodonews.net/news/2021/02/6437947c3d50-suga-apologizes-for-glitch-in-japans-covid-19-contact-tracing-app.html

A contact tracing app dubbed "COCOA" in Japan has failed miserably on
Android phones since September update, but obviously no one at the health
ministry or the development company who contracted the work verified the
operation on a real phone despite there are SNS posts of Covid-19 patients
who mentioned that their family members' phone did not report the exposure
warning at all.

I think the issue is due to a few factors.:

- Apple/Google publishes so called Exposure Notification API and implements
its functionality on their respective OS. The specs from two companies
disagreed on a few minor points.  Obviously, there have been updates, and
new specs are hard to read as many in ICT industry can attest. This type of
specs is read only by geeks and not many complain loudly that they are
written poorly. But I digress.

Only some really serious developers noticed the subtle difference between
the API published for iOS and Android.  A blog in Japanese about the bug. It
refers to the github issue comments that first reported the issue from
programmer's point of view.
https://zenn.dev/zipperpull/articles/20210210-cocoa-bug  (in
Japanese).

- Apple/Google have asked the health authorities of countries/regions only
one such app is used in the region. This I suppose is due to the privacy
concerns.

This made the selection of developers a bit difficult since there had been a
few independent groups who already have more or less working samples. (I
don't know if they were bug-free or not.).  Eventually, one of the developed
software was chosen as the basis of COCOA and a maintenance company was
chosen whose main function, it thought, was the operation/maintenance of
anonymous patient database (anonomized by apple/goole algorithms, I think.)

But actually, due to the API change over the long run, the app needed to be
maintained as well for both on iOS and Android. Somehow the Android update
got buggy but no real world phone tests did not take place if I understand
correctly. This is probably due to the unpreparedness of the development
company, but I am not sure.

If this were an ordinary software bug, I would say"OK, a bug is always
there, let's fix it and move on.".

However, when the app was relied on the health authority of the region where
I live (Kanagawa prefecture), it is not such an easy-to-ignore bug.  The
authority stated in early January, citing lack of man-power, that it would
rely on this failing app to keep track of people who come into contact with
known Covid-19 patients instead of human-based tracing.  This means that
those who relied on Android version of the app got short shrift and worse.
I am not even sure if iOS version is working correctly since there has been
a report from an iOS user who got Covid-19 and yet her family members
iPhones did not report the exposure. Hmm...

I use Android and have removed the app for now.