The ODIN mobile app can be downloaded from the Google Play Store or the Apple App Store. Please search for ConnectWithODIN in either store and choose Download.
Direct links are below.
Apple App Store
https://apps.apple.com/us/app/connect-with-odin/id1462212174
Google Play Store
https://play.google.com/store/apps/details?id=com.connectwithodin.odin