Your data is your own. We have no access to it.
By default Kluz stores your data (photos with creation dates and their descriptions) in CloudKit. If you do not wish to have your data stored in the cloud you can disable iCloud integration for Kluz1.
To delete all Kluz data locally and from iCloud follow these steps:
: You can disable this integration by opening iPhone Settings app → iCloud Profile → iCloud and unchecking Kluz.