The apple app store has the free "Bump" app which is quite popular. I personally like iFile on Cydia as you can transfer any file as well as browse, copy/move/change permissions/etc. iFile has a web server built in to transfer files too.
Saved pictures are in private/var/mobile/media/DCIM/100Apple or something. And other pictures are in private/var/mobile/media/photos I think (I don't really have any other photos than my saved photos) then just select them and click the Bluetooth icon. And it will search for other devices with Bluetooth on. (the other device needs ifile to be on in order to receive files) then u should be able to figure it out. To save a file to your photos app just open it in ifile and click on the export button on the bottom.