Korean Joyfriend offers a small mp3 player with integrated GPS.
The Joyfriend mp3 player measures 65x110x20mm and features a 128x64px FSTN display. 128MB memory is built-in.
Not quite sure how useful the navigation functionality is on this low-cost mp3 player. It definitely does not support graphical maps. AkihabaraNews has more photos and writes that the JoyFriend mp3 player sells for about $128.
Usually the Korean hand-held devices that feature GPS are also portable media players like the Digital Cube iStation i2.
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