This is the 4713th most frequent Swedish word.
appen
"Appen" means "the app" in English.
Here, 'appen' is used as the definite form of 'app', referencing a specific mobile application known to the speaker and listener.
Appen fungerar perfekt på min mobil.
The app works perfectly on my phone.
In this sentence, 'appen' again denotes the definite form of 'app', referring to a specific app that was downloaded.
Jag laddade ner appen från butiken.
I downloaded the app from the store.
Here, 'appen' represents a particular app inquired about in the context of the discussion.