App starts crashing consistently due to a bug in the background processing of the Dropbox auto backup feature.
This issue is happening on iOS 10.3 when there are non-english characters in the notebook name that is selected for Dropbox auto backup. This will happen for languages such as Japanese, Spanish, German, Chinese etc..
We're working on a fix for it as we speak and will be submitting an emergency release shortly today. In the meanwhile the update goes live, as a workaround to solve the crashing, you can either rename such issue titles of the notebooks in the Dropbox auto backup list. Or, you can just sign-out of Dropbox account. Apologies for the inconvenience caused due to this.