CLZ Cloud is a free service for storing and backing up your collection database in the cloud. It is also the recommended way for syncing data between devices, e.g. from your Windows or Mac software to your iOS app, but also between iPhone and iPad.
If you own multiple devices, e.g. iPad and iPhone, you will need a free CLZ Cloud Account so that you can sync data between your devices.
Using the CLZ Cloud service is free for everyone, including Pro edition owners, Standard edition owners and owners of the mobile apps.