You Must Promise. To call your mother, to help old ladies cross the road, and to turn your cell phone off at the movies.

So far in these articles, I have only dipped a toe or two into Aqua's pool. I have covered basic aspects of building an Aqua-compliant application, including the building of photo-illustrative/3D application icons. Now it's time to address other components of our Mac OS X application.

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.

Adopt Sheets. I really like the use of Sheets in OS X. The use of Sheets lets me know which window my dialogue belongs to without hijacking my system.

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.

So far in these articles, I have only dipped a toe or two into Aqua's pool. I have covered basic aspects of building an Aqua-compliant application, including the building of photo-illustrative/3D application icons. Now it's time to address other components of our Mac OS X application.

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.

To put my money where my mouth is, in each new article I'll build a hypothetical application that illustrates the guidelines I'm covering. Today's application is called "Paint" and will be based on the photo-illustrative icon I created in my last article. Together we will complete each step, and by the end of the project we should have a well-designed, 95%-100% Aqua-compliant application. I'll leave some room for personal preferences and the fact that Apple changes the OS every few months.

But limit your animations to whatever is required to communicate the necessary information. Avoid annoying animations that discourage ease of use. Ask yourself, "What do I need to show the user, and what is the cleanest way possible to achieve that?" A good example is the Mail application for Mac OS X. Whenever a new message arrives, the Dock icon changes appearance to indicate a changed state.

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