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.
ReachOut - ReachOut is a field service management suite to streamline field processes with customizable mobile-based forms and workflow.
Dropbox - Online Sync and File Sharing
DeltaSalesApp - Field Sales Force Automation & Field Force Tracking Software
Google Drive - Access and sync your files anywhere
Service Cloud Field Service - Service Cloud Field Service is a cloud-based field service solution designed to initiate customer service activities from anywhere.
Mega - Secure File Storage and collaboration