Developer: Dropbox
Cost: Basic version is free for 2GB storage; pro versions are $9.99/month for 50GB and $19.99/month for 100GB
We all own so many gadgets that it can be tough to keep track of which files are on which device. Dropbox aims to solve that problem with a single, secure place for all of your computer files so they're backed up and accessible wherever you are.
Add a file into the Dropbox folder on your laptop and it will automatically appear in folders on your iPhone, desktop, work computer, or wherever else you'd like. The files are also accessible through the Dropbox Web site, so you can grab the stuff you need even if your own device isn't handy.
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