There are still a few reading apps that still have store links and are still in App Store:
- bluefire reader (and the BAM clone)
- txtr (and at least one of its clones)
For the time being, I'm not updating Kindle or Google Books apps.
I'm finding that Inkmesh works reasonably well on my iPod Touch in terms of finding books in the various ebook storefronts, comparing prices etc., and launching the respective storefronts (except for Google Books) to purchase or get more information. I'd actually pay for an iOS app that did this with a more refined UI. Apple would no doubt find some reason not to approve such an app, but it's not clear to me how it would violate their terms.