Favorite iPad Portfolio app to display organized images?

[3d]

I'm in search of an offline portfolio app for the iPad to showcase an organized group of images (jpgs). Ideally it will have about 6-8 buttons/tabs/folders that someone presses to see the specific category. And then within each category there will be about 10 examples. And maybe a homepage to start?

I cannot count on wifi/cell connection during presentation. So this app will need to work offline. All images saved within the app.

I see some called: Portfolio for iPad, Foliobook, Portfolio Pro, etc..

Any favorites?