One of the many new software developments announced today at WWDC was iCloud Drive. iCloud Drive is a bit like Dropbox, as it allows you to store files in the Cloud and access them anywhere you like.
All of your apps used with iCloud Drive get their own folder, which you can access in Finder. The main perk: you can sync this across OS X, iOS, and Windows. If you're on an older Mac that doesn't support iCloud, you can still drop in files to sync them across your other devices.
Steve Jobs always wanted a Dropbox killer, but this might be too little too late. The main issue comes with cost also. Even though the price will be decreasing, Dropbox and Google Drive will remain less expensive, but just barely. With Apple, you get 5GB for free, then 20GB is an extra 99-cents a month. This is a big decrease, as Apple used to charge $8 per month for 50GB in Cloud. Google offers 100GB for $1.99 per month. Dropbox give you 2GB for free, or 100 for $9.99 a month, or less for a yearly contract.
As an added push for iCloud Drive, Apple introduced Mail Drop, which allows mega attachments that were previously too big for inboxes to handle.