First and foremost your data is secure. As your data passes through your cloud account database in our dataacenter it is always transmitted via 128-bit SSL Encryption. While we do keep a mirror copy of your calendar and contact data, it's stored in its' own database, not co-mingled with other user's data in a giant database warehouse. We never mine, sell, and/or give your data to anyone. We won't even look at your data unless you specifically ask us to in a support-related matter. We know for a fact that is not the case with Google, Microsoft and/or Apple. There's plenty of evidence to support the fact that they are actively mining data for personal and external uses.
Second, your data is always kept on your local devices, both in Outlook and your mobile device. We merely keep a mirrored copy of your calendar and contact data for the purpose of comparing what is new, what has been modified, and what has been deleted so we can keep your devices and computers in sync.
Finally, a nice benefit to having a mirrored copy of your data in your cloud account database is that we provide you with a mechanism to securely access the data in an Outlook-style inteface from an Internet connected web browser. Thus, if you are out and about, drop your phone in the pool while miles away from your desktop, you can gain access those critical appointments and important contacts with practically any Internet connected device.