Comic Zeal Comic Reader 4 ($7.99) by bitolithic is a fully-fledge comic book reader for your iPhone and iPad.
You love comic books, and you have an iPad (or iPhone), right? Did you realize that combining these things would make one of the best things ever? Comic Zeal gives you a great iPad/iPhone comic reading experience.
The first thing you need to do is to load up your comics into the app. There's two ways to do this: File Sharing via iTunes USB connection or wirelessly via Bonjour or similar servers. I found the File Sharing option in iTunes to be the easier route since I wasn't able to figure out the wireless way.
Once you get your comics loaded in the app, you can view all of your comics with the Collections tab, and any recently read comics will appear in the Recents tab (this is missing on the iPhone). Comic Zeal also includes some free comics you can download in the Featured tab, which will then show up in Downloaded as well as Collections.
The Settings tab has a plethora of different settings, so you can customize your comic reader to your geeky heart's desires. For those that are into mangas, there's even a manga mode that can be toggled (right to left) since the default setting is for regular comics (left to right). I have not tried out the manga setting because I do not have any mangas on my computer, so if you get the app and use it, help us out by commenting on how manga mode is!
The bottom menu bar includes an option to take a screencap of the comic image (better than the power + home button because there won't be any trace of the app in the screenshot) so you can instantly save a cool scene for your wallpaper or whatnot. If you prefer to have your comic reading done in a certain orientation, the app has its own rotation lock, which is a bit more convenient than the default way of doing it for the entire device.
If you're done reading, there's an eject button. The arrows are for turning pages, although you can simply tap the left or right side of the screen to turn pages as well. You can see your progress through the comic with a little scrubber beneath these buttons. It doesn't tell you what page you're scrolling to though, so watch out for that.
Now, when you read, you can either hide the menu bar or keep it displayed. To do this, just tap that small little arrow at the end of the top menu bar. You can now read your comics the way they were meant to be read - digitally on the iPad (or iPhone). If you need the menus back, simply tap anywhere on the screen or the arrow.
I found the experience of reading comics on Comic Zeal to be one of the best yet. It's clear that the iPad is made for reading books (with iBooks and all), but comics and magazines have fully utilized the iPad as well. The iPhone version of this app is also well done, however, it's clear that this was made for the iPad experience. Everything is just much more squished on the iPhone.
But the best thing about the iPhone version is that you can always pull out a comic and start reading, even if you have to zoom in a bit, depending on the image quality. Either way though, Comic Zeal brings comic perfection (or at least pretty close to it) for your iPhone and iPad.
If you want to add comics to your 'practical uses for an iPad,' then do yourself a favor and pick up Comic Zeal. I cover the universal version which is $7.99, but there is an iPhone-only version called Comic Zeal Comic Reader Mini available for only $3.99.