Can I add metadata to a jpeg in Android? Does anyone know of a way to take jpegs imported from my camera onto my Android tablet then add the metadata properties that Windows calls Title, Tags (I assume, possibly wrong, that this is Keywords in EXIF terms) and possibly Subject so that they are there when I eventually transfer the photos to  Windows PC?

Any help appreciated.
There are several exif editors in Google Play. One of them is EXIF Tag Editor (Photo). 

As suggested by Izzy, there are also gallery apps that can do this:


JustPictures!
Photo Mate


Note that the latter two apps are no longer available on Play Store.