When you log in to your EasyLaundry account for the first time, you need to have created an account at www.vasketid.dk and received your tag.
Download the EasyLaundry app from the App Store or Google Play.
In the laundry's payment system, scan your tag and click on the "My account" section. Then click on "Create app key" and fill in your phone number.
After this, you can open the app and press "Download app key" under settings. Fill in your phone number and press "Download app key". The App ID, username, and password will now be imported into the app, and it is ready for use.
From now on, when you want to log in, use your username and password just like when you visit the site at www.vasketid.dk.