For hosting common files it's ok. Also it is on Android too do, great to transfer files between your Windows and your phone. But if you want better security you have to subscribe a monthly offer.
fastlane - Connect all iOS deployment tools into one streamlined workflow
Dropbox - Online Sync and File Sharing
SimPholders - A small utility for fast access to your iPhone simulator apps.
Google Drive - Access and sync your files anywhere
Salesforce Mobile - Run your business from anywhere with Salesforce Mobile. Access info, reports, and take critical action anywhere, anytime. And use a variety of CRM apps and plugins to do more with your business on your phone.
Mega - Secure File Storage and collaboration