Homebrew dev pipagerardo has released a Lua-coded 1945 clone for the PSP. Version 1.0 currently sports 11 different enemy types: 9 aircraft, a ship, and a submarine.
You can play 1945 v1.0 as a sidescroller or as a vertical shooter, but for the latter you'll have to contend with some tricky hand positioning as the shoot and bomb actions are bound to the X and O buttons respectively. Movement is done by using either the d-pad or the analog stick.
It's a rather fun little game, especially the bundled music, which you can change with the L trigger. 1945 v1.0 also includes support for up to 9 different mp3s, so you can put in whatever music you want. Other features include a screenshot option (R trigger) and editable levels.
Download: LUA 1945 v1.0
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