So there are several apps on my "frequently used" list that are dedicated to particular vendors or brands. On the list I published earlier, I included amazon, netflix, and comcast. In fact, I'm pretty sure that Phone Flicks is a third-party app, but it only connects to my netflix account, so for my purposes it isn't much different than the other two. Here's why I like each of these, and why I use them.
The amazon app is useful because amazon is my most likely source for purchases that I can't make locally. It is very handy to have them "in my pocket", because I can purchase something on the spot. In other words, I can go to Hastings Stationer, or Cowls Lumber, or Food for Thought books (my three favorite examples at the moment), and check for whatever widget or volume I need. If I can't get it from them, I pull out my iPhone, and purchase it that way. It is still off my To Do list (see earlier post) at that moment, either way.
Phone flicks is great because it allows me to put something on our cue (que? How do they spell it?) right when someone mentions a film or show to me. Of course, my tastes in such things are falling right off the radar of the rest of the world, so it may be of diminishing utility ;-) (child abduction? nope, can't watch those any more. Infidelity? not interested. Too much realistic blood? Sick people? Death? Sounds like work, not entertainment. Just plain jacks my blood pressure? No time for that. BBC farce? *perfect*). I just installed the app for the IMDB (internet movie data base) so those two should work together well. I haven't used it much, yet.
The Comcast app is great because it makes our comcast voicemail into visual voicemail (text listing of what numbers the messages are from), from anywhere. Nice! I've gotten used to that on my iPhone, now I can have it for my home phone, too. I use it for TV listings, occasionally, but not that often (see above). And I don't use comcast email much, but if I did, it includes that, too.
I downloaded the ebay app, but I just don't use ebay that much. It is nice to be able to track the progress of auctions, so for those who use ebay a lot, it makes good sense.
You may have favorite apps in this category, to go with favorite vendors. Please post any suggestions (or warnings about badly designed apps) in the comments!