If you've encountered an issue where you have opened the app to find either a plain white screen, or a dark patterned screen and are unable to progress to the login, the below steps will help to get the app working again.
1. Open the Settings on your phone
2. Select Apps (alternatively Apps and Notifications on newer versions of Android)
3. Select the Lookout app to open the App info.
4. Open the Storage section
5. Select the Clear Data button and select OK to confirm
You should now be able to log in to the Lookout app.