What is Typing Jet?
Typing Jet was a Java typing game released for Japanese mobile phones in 2001. Players avoided obstacles and ran from the police by quickly typing characters.
It was unveiled alongside other mobile titles such as Ulala's Channel J (Based on Space Channel 5), Columns Jr., and The Typing of the Dead.

What about De La Jet Set Radio?
There was a game called De La Jet Set Radio, but it wasn't a Java mobile game. It was a re-released version of Jet Set Radio sold exclusively in Japan through Sega's Dreamcast direct service.
It included the extra levels, music, and characters from the European and American releases, along with several bug-fixes.

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