Make sure you’ve updated your Facebook app to the latest version and then go to your profile to update your profile picture.
When you select a photo to upload, a little clock icon will appear on the Crop & Rotate screen.
Tap it to select when your profile should expire.
When you visit your profile, you can see when the picture will expire.
Once it expires, it returns to the previous photo you had set as your profile picture.
One reason this feature is a good idea is because profile pictures on Facebook have been public for a while now.
Say you were to upload a sonogram, or a picture of your degree to share with friends and family. You will not want to keep it public for too long as it’s sensitive information.
In that sense, the feature is awesome since it removes the information automatically.
Temporary profile pictures haven’t been rolled out for Pages even though they could probably benefit from the feature more, if not equally.
Pages could use it as a means to advertise time limited promotions they have running but Facebook likely prefers that people buy ads to do that instead.