Dropbox is an easy to use freemium cloud storage solution. It has a client sync utility for multiple platforms.

MEGA is the cloud-based file hosting solution.

Resilient, fast and scalable file sync software for enterprises and individuals.

Gladinet is an on-premises, enterprise file synchronization and sharing (EFSS) platform.

Microsoft OneDrive is a cloud-based storage solution from Microsoft.

Box is an online file sharing and content management service.

Koofr offers safe EU based cloud storage with 2 GB free cloud storage space for life and options to connect multiple cloud accounts.