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.
Nexmo - Nexmo is a simple two way SMS API with global reach and wholesale rates
Dropbox - Online Sync and File Sharing
MessageBird - Reach 7 billion phones in seconds via SMS, Chat & Voice. Try it for free and improve your communication.
Google Drive - Access and sync your files anywhere
Plivo - Plivo simplifies your customer engagement.
Mega - Secure File Storage and collaboration