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
Waddle Photos - Meaningful stories about your children.
Google Drive - Access and sync your files anywhere
Toca Boca - We make digital toys from the kid perspective.
Mega - Secure File Storage and collaboration
MentalUP - Entertain and test your children with >120 games