It should be noted that it also gives the folders a much more native feel, with SpringBoard-like anti-aliased text, etc. CategoriesSB is well worth the money for anyone who uses Categories.
I didn't want to start my own thread... I have an iPhone2G I am trying to add folders to.
It is on 3.1.3
"Categories" is an option although a poor one if I can't also purchase "CategoriesSB" as an add-on that allows the first tweak to run more like an IOS feature.
"CategoriesSB" is no longer being supported (although why it is offered in Cydia then is beyond me) and within the description page refers to "Folders" as an alternative.
"Folders" tweak isn't supported with 3.1.3 leading me right back to the starting gate.
I was hoping there is another workaround and/or app or tweak that will equally get the job done.
Found a better fix though! Lots of looking around...
Added this repo: http://www.repod00r.com and found a tweak (whited00r 5.0) that allows me to add IOS5 features to 3.1.3
(iPhone2G had to be booted twice after install!)
Within that is the folders option.