The woman behind Glowfly is Heather Beaman,and she has designed,as she calls it, a "Brilliant chord chart" for ukulele. (There are also charts for mandolin,guitar,and banjo-just so ya know) What I love about these charts is it makes basic chord theory and explaining scales so darn easy to understand.
As a banjo & mandolin teacher,believe you me,I get amazed at how beginners can either over complicate basic theory and struggle to understand concepts such as figuring out what basic chords are in a given key. Well,for those of us who learn best by visuals (I'm one of those!) take a look at her Kickstarter page- and watch the cool video that shows you her awesome design:
Glowfly Kickstarter Chord Charts-Click 4 Video!
Here's a closeup of one of the pages from the Ukulele chord chart. Notice how easy it is to see and understand the basic I,IV,V as well as more complicated info. She makes chord charts as well as scale charts (as mentioned in the video you watched- (you did watch it,right?)