Kuwanger has released a new unofficial version of pogoshell which works on the GBA and also the DS, heres all the info:

Pogoshell is a file manager for the Gameboy Advance. Really, that's an oversimplification. Pogoshell also includes a much better save management system than most flash cart frontends provide. Another big feature is plug-ins, a system of loading files through an association system. Finally, Pogoshell supports a theming system, offering a much more customable interface.

With the development of Pogoshell v2.0b4, official development of Pogoshell has stalled. While there was a Subversion archive setup with work towards, assumedly, a v2.0b5, the work was never completed towards an official release and doesn't properly work when simply compiled. With v2.0b4's source unavailable, I decided to continue work using v2.0b3's source. So far, this has meant merging in some changes from the Subversion archive, changing theme support in many ways, and removing a few limitations to things like file listings. For a move complete list of new features, look below. Note, internal mod player support had to be removed, as the license for it required permission to redistribute, and I personally didn't want to require others to ask permission to make their own forks.

Features (above Pogoshell v2.0b3)
Maximum of 500 files per directory
Internal JPEG viewer
Internal encrypted JPEG viewer
Internal apack compressed multiboot support
Hidden directory support*
Theme Switching support
Improved Theming options*
Screeensaver support
Limited list position tracking between directories/games
Fixes some close() bugs
Easier list movement with left/right
Font truncation (to avoid writing writing outside of a widget)
And others I'm forgetting
*Features incompatible with either Pogoshell v2.0b3 tools or with v2.0b3 themes

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