Joel16 has updated his Shell App for the 3DS:

Before installing this update, please delete your config file located in /3DS/3DShell/config.cfg. This release will automatically handle this for you in future releases if entries are modified in the config file. You can also update straight from 3DShell, by tapping the download icon (Updates menu) and updating via the official release build option

Minor clean-up with audio functions, config file and .ZIP extraction, removed deprecated functions. (Also built using the latest citro2d and libctru.)
Improved music lock texture.
Added battery icons to status bar.
Add ability to extract .RAR archives.
Add "More..." option in file options.
Added the ability to refresh directory list.
Added the ability to create new files.
Cancel button can be accessed via buttons.
Minor fixes with handling UTF-16 filenames.
Added a W.I.P text file reader for small config files. (This is very basic at the moment. I simply implemented this for reading log files straight from the 3DS).
Handle config versions (At the moment, you'll need to delete your config file located in /3DS/3DShell/config.cfg, however after this update this will no longer be necessary with future releases).
Fixed buffer overflow when selecting a file with a long file path using multi-select.
Fixed copying files/folders between different archives sd <-> nand.
UTF16 file names are now properly handled when copying/pasting files.
Added the ability to zoom into image if < 400x240. (c-stick or D-PAD to zoom, circle pad to position image).
Improved executable file icon. (The previous one didn't work well with the dark theme mode).
Added an error display dialog if any issue occurs with FS or archive related functions.
Fixed OPUS support.

If you'd like to support me, then feel free to buy me a coffee, I'd really appreciate it!