Dropbox
Dropbox is the original cloud storage app and is still, arguably, the best. With native apps for all mainstream desktop and mobile platforms, Dropbox makes it easy to access data regardless of location. The company, faced with stiff competition from Google Drive, Microsoft Skydrive and others, is also looking at adding social functions to its core storage product.
www.dropbox.com. Free base level offering. Tiered pricing for additional storage.