I have the ebay app on my (secret) iphone. I find it hard to read and geared towards buyers.
Alternatively, I have the amazon ipad app on my unsecret ipad (ipad one. *sigh*)
I find it much better, even better in some ways that the actual web page. Eg when you can delete things in your cart without having to delete one at a time due to being taken back to the top of the cart list.