Well, definetely worths 1.99.
This is the first app for iPhone allowing you to test 3D page turning feature available exclusively for iPad.
Interface:
Its just simple and beautiful. You have main info and options under your hand.
It has some reverse side of coin: item downloading view is a bit ugly(especially on iPad), devs need to redesign it.
Usability:
You can redefine tap zones to vertical or horizontal.
As for me, "dead zone"(where pages dont turn, instead you have some info about book and some options) is a bit small. Instead of showing options I sometimes turn the page.
Rendering:
iPhone version is just beautiful! iPad version is a bit ugly, you see these polygons and non-real shadows.
But these bugs are nothing comparing to readMes advantages ;)
ZeFiR about readMe