[Important Notice] Malfunction with the iOS app which requires "Additional Sign-in"
Thank you for using BOOK☆WALKER.
On September 25, 2018, BOOK☆WALKER app has been merged with the Niconico Book app.
Due to this merger, there is currently a malfunction with the iOS app version 5.0.0 to 5.0.1, which requires "Additional Sign-in" even if you do not have a Niconico account.
In such case, please follow the steps below to fix the issue.
1. Update the app to the latest version (version 5.0.1)