When you use Camera Upload, Dropbox automatically changes the names of your photos to reflect the date and time they were taken, such as:
Why does Dropbox do this?
Many cameras and mobile devices will name photos with sequential numbers, such as:
This can cause problems later if those numbers are used again for different photos, such as when the sequence rolls over or you start using a new camera or SD card.
By changing the name of each photo to the date and time it was taken, Dropbox gives your photos unique names and enables you to tell them apart in a more meaningful way.