"Invalid or null criteria specified" error message

"Invalid or null criteria specified" error message

As of today 2 separate apps showed the message "Invalid or null criteria specified" when submitting and entry using the mobile app. The two apps had been working properly and no changes have been made. Has there been any changes on Zoho´s side that might be the cause? Can anyone find an explanation or possible cause for this?
Thanks in advance
Constantino