My very first iOS device was a 16GB iPhone 3GS. I was in love with that phone, and it still holds a (smaller) place in my heart. Since then I have had an iPad (first gen), iPad 2, iPad (third gen), iPhone 4, iPhone 4S, and iPhone 5.
I prefer paid apps to free apps. Paid apps are almost always better than free ones because they (in most cases) provide a better experience through design, usability, and content. Due to this ideology, I have downloaded many, many apps. The iPhone has really changed what I feel is good software. If an app doesn't have an attractive icon, I look elsewhere. That is the very first thing I look for when I buy an app.
"Is the icon ugly?" I'll think to myself. Due to the structure of the iOS home screen, I will be constantly looking at it, so it has to look nice. If the app in question has an attractive icon, I move on to the description of the app. Does the app do something that cannot be found in my current collection of apps? Does it do it better? Is it capable of doing multiple features, or just one really well?
Finally, I move on to the screenshots. This is where most apps are forgotten. I don't like ugly UI, and I often won't download apps that I find to be ugly, even if they are useful. I definitely won't pay for a ugly app.
I consider the user reviews last, because, they are often unreliable. Most people don't know how to read, and therefore, leave shitty reviews. These are the same people that review microwaves on Amazon, and leave bad reviews. "I had to put my popcorn bag in the microwave before it would cook it". "I had to plug the microwave in for the clock to come on".
If you feel I am exaggerating, open a new tab and read some of the lower star reviews on Amazon. I'll be here when you get back. Another reason I don't read the reviews is because in some cases, it is fairly obvious that they are from the company that developed the app. Granted, this isn't always the case. There are exceptions and some reviews can be very helpful.
Okay I'm rambling now. Here is a list of my favorite iOS apps. I will do universal apps first. The universal list will include apps that are universal binaries (buy once for both iPad and iPhone/iPod Touch) and apps that while they aren't universal binaries, offer both versions.
Bare in mind that these prices were current at the time of this posting. I have written very crappy descriptions of the apps I have included in this list, sorry about that. I do assume however that if you wanted to know more about an app that you can open the link and read more there :). Finally, this is in no way an exhaustive list of apps that I have purchased, or apps that I like. It was a list that I felt were the best paid apps that I had encountered at the time of this writing. I will update this post in the near future with more apps. Enjoy.
Universal Apps (Both iPad and iPhone/iPod Touch versions of the app)
I'm going to start things off with some note taking apps, as I am addicted to them.
Awesome note (This is one of those apps that has both iPad+iPhone versions, but isn't a universal binary) This is by far, the best note taking app that I have found on iOS. It is very neat, and organized and it has lots of options for organization.
NoteFile is a no frills note taking app. It is very, very simple, but that's why I like it. If I need to just typing something really quick, Noteflile is great.
Delivery Status is a great way to track packages on iOS.
Tweetbot A full service Twitter client.
Netbot A really good App.net client
Flight Tracker Pro , a super easy way to track your flight.
iFlies is an incredible file opening/viewer app.
iStudiezPro is an organizer, calendar, assignment book, and more for high school and college students.
Pages is a word processor from Apple.
Keynote is an app from Apple to create slideshow presentations.
Numbers is an app from Apple to create spreadsheets.
Soundhound is a great way to identify unknown songs.
Tapatalk is a great app for those that like to browse forums.
1Password is a password keeper.
BeejiveIM is an instant messaging client for iOS that handles multiple logins and platforms.
Djay is a DJ app for iPhone and iPad.
Camera+ is a great camera app.
Reeder is one of the best RSS feed readers I have found on iOS
iPhoto is a decent photo editor
iMovie is a good video editor for iOS.
Garageband, for me, is just something fun to play with.
Drafts is a great way to enter text quickly and send it to a variety of apps
Blogsy is a very powerful blogging app that works with many popular platforms.
#Pan is another full-featured App.net client. The price is a little steep, but the app comes with it's own dedicated hosting service for media, which is a plus.