Not Icelandic.
This app does not teach icelandic vocabulary. It teaches dzongkha which is not even close to a norse-based language.
Not enough ratings yet to assess Icelandic Vocabulary Exam.
Icelandic Vocabulary Exam appears to be a legitimate app. AppsHunter Legitimacy Score for Icelandic Vocabulary Exam is 80/100.
Based on 80 of 100 points across 7 verification signals from App Store and developer data.