I see lots of brands advertising “Hey, download our mobile app and…” …and you will have a menu with 5 items. The most complex item probably will be a form with 3 o 4 fields and one submit button. Ah, with a success message!
– Do you really need a mobile app?
– Sure! I need user location and push notifications for some requirements.
The main advantage is obvious: you will code only once. Also, you will skip Google Play and App Store submission.
Remember KISS: Keep It Simple and Stupid