SpiderOak (Android, iOS)

If you have been using dropbox.com for cloud storage, you may have heard they were recently hacked and your username and password may have been compromised. If you're seeking a more secure way of storing and sharing your files, check out SpiderOak.

Their biggest selling point is "zero-knowledge privacy", which means they have no idea what you are storing on their servers and no way of finding out.

SpiderOak provides military grade, end-to-end encryption; data in transit and being stored are fully encrypted using a password you select. The downside? If you lose or forget your password, you have also lost your files.