If you use Dropbox to store photos and save space on your iPhone or iPad, there may come a time when you want to share those photos to a social network or with a friend. In order to do so, you'll most likely have to save them to your camera roll first.
As it happens, Dropbox gives you an easy way to do this. Here's how:
Launch the Dropbox app from the Home screen of your iPhone or iPad.
Find the photo that you'd like to download to your camera roll in your Dropbox app.
Click on the Download button in the lower right hand corner.
Now tap on the option for Save to Photo Library.
The photo will export directly to your iPhone or iPad camera roll.
Once the export is done you can hop right into your Photos app and upload it to whatever service you'd like.