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.
Dropbox - Online Sync and File Sharing
Voxer - Turn your phone into a Walkie Talkie. Don't waste time on phone calls and voicemails.
Google Drive - Access and sync your files anywhere
NextPlane - NextPlane offers cloud-based, scalable unified communications federation service for the enterprise.
Mega - Secure File Storage and collaboration
Sameroom - Chat interoperability-as-a-service