apps-android-wikipedia VS Alarmio

and theirs also the Wikipedia app which is open source. Here's the GitHub page, [https://play.google.com/store/apps/details?id=org.wikipedia](and here's the google play listing)

Here is how the Wikipedia Android app handles that use case. It's in Kotlin, but it should give you an idea of how to implement.

I am aware of it. On Google Play you may encounter money demand, but in F-Droid or GitHub releases you just simply cannot. Note that Alarmio is not still maintained but when I tested it I did not encounter any issues with it, so I acknowledged polished experience rule.

On Google Play it is not but on F-Droid and GitHub it is.

Then you don't have to lock your phone to disable it. The fact that it hasn't been updated does not bother me. It is just an alarm clock which functions properly at least in my phone. But I can understand if you don't want to use it. In such a case, you can try Alarmio, Clock+, or Simple Alarm Clock.