Continuing along with the "Essential apps" line of posts, today I'm want to delve into what I think are the best and most essential Mac OSX applications. Let's jump right in.
Web browser: Chrome
Safari is a pretty great browser, all things considered (it certainly beats Internet Explorer when you are comparing default browsers between Windows and OSX), but Chrome is a tough competitor to beat. It syncs seamlessly with all your Google apps when you log in, can sync bookmarks across multiple devices (including mobile devices), and is one of the fastest browsers (depending on what you're using it for), and it all comes with a $0 price tag. Chrome is tough to beat.
I wasn't always the biggest fan of iTunes, but with the latest release (version 11) I have been very impressed and really enjoy using it once again. If you have an iOS device, you simply can't live without it either. The best thing about iTunes is probably the iTunes store, so you can purchase music right from the program and access it through iTunes, rather than having to purchase CD's or download via Amazon music store and load the songs into other music apps if you're not using iTunes.
Code editor: SublimeText 2
There are quite a few (very good) code editors for OSX, but my pick is SublimeText 2. This might be different if I didn't do development on both Windows and OSX, but since I do, Sublime is tough to beat because it has apps for both Windows and OSX, and they use a shared license so you only pay for it once. The down side of this app is that it is fairly pricy... $70 is a lot for a program, but if you write code a lot you will not be disappointed (not to mention many competitors also have high price tags on their software as well). Other great options are TextWrangler, XCode, and TextMate. If you only use OSX, I would recommend a trial of each of these to see which you like best (Sublime has an unlimited free trial but they will bug you to keep buying, TextMate has a 30 or 60 day trial, I can't remember which it is).
I use Tweetbot on my iPhone and iPad, so I was really excited to try out Tweetbot for OSX, and I was not disappointed. I was using the official Twitter app for Mac prior to switching, and was pretty happy with it, but once I switched there is no going back. Tweetbot syncs your position on your timeline across all devices, so if you haven't checked twitter on your laptop for a few days but just checked on your phone two hours ago, Tweetbot will remember where you are. This alone is worth the price for me. $19.99 unfortunately is a high price for a twitter app, but if you use the iOS apps, I promise you won't regret spending the money.
Email client: Mail.app
The default mail app is pretty good. I personally use Gmail on my laptop for personal email so that I can get my mail anywhere (I use Mailbox on my phone), but for my Exchange account at work I use Mail on my laptop. I was using Outlook for a while but I found it to be a little buggy and have had more success with the default app. If you're looking for a desktop mail client for Exchange accounts, look no further than the default app. However, I highly recommend using a web client for your personal email since you can access it anywhere.
Instant messaging: Adium
Adium is a free chat app that can log into many different services and lets you chat with buddies across multiple services at the same time. I primarily use it for Gmail chat, as I prefer a desktop chat app over the in-browser chat Gmail provides. I have found it quite annoying to use if I have both Adium and a Gmail tab open though, so I usually close out Gmail unless I need to check it. There are plenty of IM apps but Adium does a great job and allows you to log into multiple services at the same time.
App launcher: Quicksilver
If you don't use an app launcher, I can't recommend one highly enough. I didn't use one until a few months ago and I have been so happy that I started. A quick keyboard shortcut brings up a search window. From there, you just start typing the app you want to launch. You can either launch the app or search for files within that app (for instance, songs in iTunes). I still keep my most used apps in the dock, but lesser used apps I launch using Quicksilver. Try it out for a week or two if you've never used one before.
Note taking: Notational Velocity
I am a Simplenote user, but Simplenote does not have a desktop app. Notational Velocity syncs with my Simplenote account and lets me create or edit notes from my desktop. It is very quick, clean, and easy to use. If you're a Simplenote user I can't recommend Notational Velocity highly enough. If you don't use Simplenote, I suggest you try it out.
To Do: Wunderlist
I spent years looking for the perfect to-do list app and finally found it with Wunderlist. Funnily enough I tried it a year or two ago and didn't like it. They recently updated the app to Wunderlist 2 and it is much better than it used to be. They have apps for smartphones, a web app, and a Mac OSX app, which makes it very easy to access your to-do's anytime and anywhere. The interface is smooth and intuitive and the app is very snappy.
Disc burning: Burn
If you're burning CD's, use iTunes, but if you need to burn anything else (.iso's to a DVD, data discs, etc), definitely check out Burn. It has a ton of options, is easy to use and understand, and is very reliable (important so that you're not wasting discs on bad burns). Best of all it is free. If you ever burn more than just CD's you should definitely check out Burn.
Read it later: Pocket
Pocket is a great tool that is available for iOS, Android, and Mac OSX (there's also a web app). If you're ever reading through twitter or on a site and see an article you want to read but don't have time right now, Pocket has the answer. You simply save the link to Pocket and next time you open the app, you see a list of all articles you have saved to read.
I'm relatively new to Mac OSX, so I'm sure there are plenty of apps I'm missing in this list. If you think there are some apps that belong here that I don't have, let me know in the comments!