Suggestions for making "Addons" for a CI app?

[eluser]pickupman[/eluser]
You could take a look at [url="http://bitbucket.org/philsturgeon/codeigniter-modular-separation/overview"]Modular Separation[/url]. You will also find info in the CI wiki. This allows you to put a set of controllers/models/views into subfolders.

As with addons for wordpress, the web gui just downloads the zips and then extracts the files into /wp-plugins. You could code the similar behavior where a user could upload a zip folder, and the contents are unzipped.

Give a look at [url="http://pyrocms.com/"]PyroCMS[/url]. It's built on CI and has these types of features.