If you have downloaded the Dropbox app on your iPhone or iPad, but suddenly find that it's missing, it was most likely moved into a folder on your device.
To locate the Dropbox app, or any other app on your device, you can use Apple's Spotlight search feature:
- Swipe down on the home screen, and search for "Dropbox"
- You'll be shown a list of results—if the app is in a folder, the name of the folder will appear to the right of the app