Today I'm going to cover some awesome developer tools that can make your life easier. These are listed in no particular order.
AppViz: http://www.ideaswarm.com/products/appviz/
AppViz is a tool for automatically downloading your sales, trends and financial reports from iTunes Connect, as well as the reviews for your apps. The app works by scrapping the information from the web so it breaks whenever Apple changes something at iTC, but, IdeaSwarm, the creators, are insanely fast at analyzing the changes and pushing out an update to accommodate. This is by far the best $30 I've spent, and to be honest, I don't know of a single developer with published apps, that isn't already using AppViz. So I guess this tip is for newbies. Get this app now, you'll love it.
MajicRank: http://majicjungle.com/majicrank.html
MajicRank by David Frampton (of Chopper 2 fame) is the tool to use to track how your apps are doing in the top 200 lists. It scans all regions, so you can see results in countries you can't normally access. It's similar to AppViz in that it scraps info from the web and so it can break, but it rarely does. MajicRank is free so there's no excuse not to use it.
TestFlight: http://testflightapp.com/
I mentioned TestFlight a couple of weeks ago but they're worth adding to this list too. They've created a great service so far, it's almost too easy to use! There are still some kinks to work out, but note that they moved quickly to resolve the security issue I pointed out in the last article.
DropBox: http://dropbox.com/
DropBox is a fantastic cloud storage system for users. It lets anyone backup important files or easily transfer files to another place/person effortlessly. They provide an SDK that lets you add DropBox support to your apps so that you can let your users backup and/or transfer their app data easily.
Amazon AWS: http://aws.amazon.com/
Amazon Web Services actually consists of several great tools. The two most popular so far seem to be S3 (another cloud storage system, but intended for companies not users), and SimpleDB (a simple database in the cloud). If your app is data intensive, there doesn't seem to be a better solution than Amazon for hosting that data. They now have a free starter plan too so you can try it out at no risk.
Matt Gemmell: http://mattgemmell.com/
Mr. Matt Legend Gemmell isn't really a dev tool, but he does make a few that you can use in your apps. The most popular ones are MGTwitterEngine (an implementation of the Twitter API) and MGSplitViewController (a replacement for the iPad's UISplitViewController that gives you more control/options). Check them out here: http://mattgemmell.com/source
Accessorizer: http://www.kevincallahan.org/software/accessorizer.html
I found out about Accessorizer through Jeff LaMarche who said it was one of his favourite apps. I can see why. The app is a source code generator. You teach it your coding style, and then it pumps out code for you. No, it won't build your next app for you, but it will save you tonnes of repetitive typing setting up all your class properties etc. If you value your time, Accessorizer will save a lot of it for you.
TouchXML: https://github.com/TouchCode/TouchXML
TouchXML is a library for reading in and parsing XML files. If you store your app's data and/or configuration in XML files, this is a far faster way of getting that info than using libxml. You can quickly extract exactly what you need from XML in just a few lines of code. Truly indispensable. And if you'd prefer JSON over XML, there's a TouchJSON available too.
Hopefully some of these tools will help you or a friend on your next project.