App installed from Play Store and updated through Fdroid repo. How??

[deleted]

I installed Quillpad Play Store link from Play Store in the Owner profile.
The version on Play Store is 1.4.9
Then I copied this app in a different profile.
There in my Droid-ify (fdroid client) app Quillpad is 1.4.10

Note - Quillpad is not available on any other repository but Fdroid repo.

So I tried to update it and it got updated.
But It should not get updated but actually show a warning of having signed with a different certificate.
What am I missing??

[ Just to be sure I repeated this process again.

Uninstalled Quillpad from secondary profile as well as from owner profile.
Installed it in Owner profile through Play Store.
Copied it in secondary profile.
Updated it through Fdroid.
And it got updated again.

Can anyone confirm this or
tell me what knowledge am I lacking?

de0u

[deleted] [Edit: please ignore my previous speculation, which I suspect is erroneous.]

[deleted]

It is the same app because in Owner profile in App details section before updating it was showing "App installed from Play Store", now shows "App installed from Droid-ify".

Edit - Can anyone having any Fdroid client installed confirm that the app Quillpad is only available in Fdroid repo and not in any other repo ?
App link - https://www.f-droid.org/packages/io.github.quillpad/

[deleted]

Ok so now I uninstalled Quillpad from both profiles.

In Owner profile, installed Quillpad from Play Store.
In the same profile, Updated it through Droid-ify.
And it succeeded.
(Quillpad is one update behind on Play Store)

treequell

As long as the same signing keys are used for the app in the Play Store and F-Droid repos, that is expected.

de0u

treequell As long as the same signing keys are used for the app in the Play Store and F-Droid repos, that is expected.

I thought Google uses their own keys and so does F-droid? Or are both APKs so old that they pre-date the current policies and both were signed by the developer?

Wydro

I got this app directly from Github but I just tried the F-Droid version on another profile and the installation worked. The signature looks the same. I suspect it must be one of the "reproducible builds" apps on F-Droid, signed by the developer.