No, Airnoise.io is not a mobile app. It is a mobile-friendly web application, meaning you can open it in a mobile browser on your phone or tablet and use it just like an app.
You can add an icon to your mobile device's home screen to quickly access Airnoise -- see this article for iOS and Android. Once you login to your account and check 'Remember me' on your mobile device you will be able to quickly access the application to easily generate a complaint.
We are considering building native mobile apps but since the web application works pretty well on mobile devices, that's down the list of priorities. We have a bunch of other things we want to do first.