Okay, I just told you what Apple wants you to look out for with window positions, but in the real world, not everyone uses the hiding feature of the Dock, and it is unrealistic to be able to predict where each user will place their Dock at any given day or how large they will have it. However, you can build a feature into your application that allows spacing for the Finder. You can give users the option of where to position their windows and what area of the screen not to cross. I know that BBEdit provides me with this feature, and I wish more developers gave me more control over my windows.

Whether native or not, this is obviously one of the first steps on your way to OS X. Keep in mind that often, the functionality of your code has a lot to do with how your interface is designed. How many developers have come up with great functional ideas from working with their interface or looking at their competitors'? Start working on your Aqua compliance from day one. Don't wait until the last minute.

Other examples of these animations might be to show the status of an FTP transfer, the progress of media being digitized, or an updated time signature. And don't forget that users may want to have some control over this, so give them plenty of options, including the ability to turn these functions off.

If an application is designed well, the reward for users is that they will learn it faster, accomplish their daily tasks more easily, and have fewer questions for the help desk. As a developer of a well-designed application, your returns on that investment are more upgrade revenue, reduced tech support, better reviews, less documentation, and higher customer satisfaction. The rewards of building a good-looking Aqua application are worth taking the extra time.

Adhere to File Locations. Make sure that when your users save documents, your application knows where to put them and also gives users flexibility.

In building your amazing Aqua application, one of the most important things to consider is the Dock. There are three things your app needs to be "Dock Compliant." Now, I write this knowing that the Dock will be going through some major changes soon, but for the most part, these should still hold true.

At WWDC, I listened to Apple representatives make some excellent points about taking the time to build a 100%-compliant Aqua application, and I think all developers need to look beyond the code and listen to what the folks at Apple have to say

For my Paint application, I created a series of icons to simulate a rendering algorithm. While the application is performing this CPU-intensive task, you can always see the status of the document by the icon changing in the Dock.

Adhere to Layout Guidelines. Did you leave 12 pixels between your push buttons? Does the positioning of your pop-up menus make sense, and when do you use a pop-up versus a scrolling list? Are you using the right types of buttons for the proper functions?

Whether native or not, this is obviously one of the first steps on your way to OS X. Keep in mind that often, the functionality of your code has a lot to do with how your interface is designed. How many developers have come up with great functional ideas from working with their interface or looking at their competitors'? Start working on your Aqua compliance from day one. Don't wait until the last minute.