A number of users have had their App freeze on a check-in and they have been unable to continue.
If this has happened to you then in the first instance we apologise. It is likely caused by a database crash in the system memory of some devices.
While frustrating, it is actually very easy to fix by Force Closing the App and Re Opening it.
Here is how to do it.
Apple Devices :
Home screen, swipe up from the bottom of the screen and pause slightly in the middle of the screen
Swipe right or left to find the app that you want to close.
Swipe up on the app's preview to close the app.
On older devices, double-click the Home button to show your most recently used apps then follow the same instructions as above.
Android Devices :
Open Settings App.
Scroll down and tap on 'Application Manager'
Scroll down in the 'Downloaded' list and tap the name of the app.
Tap 'Force Stop' to fully close the application on your device.
This fixes most issues with Apps.