It's not every day that a company shows off literal vacation slides as part of a press event, but Dropbox did it today as a way to introduce Carousel. It's an app for both iOS and Android that takes your photos from your Dropbox account and organizes them by time, date and event, and any new photos that you take on your phone will automatically backup to the cloud. You'll also be able to not only share all of your precious memories with family and friends, those same people can return the favor and share some of their pics and vids so you can add it to your personal deck of digital slides. The new app will be available on both platforms today for free. When we asked company reps about desktop and other mobile platforms, we were told that Dropbox is a multi-platform service, hinting that we can expect expansion further down the road without actually giving a specific time frame.