Three important aspects of your BlackBerry app are the name, icon and the splash screen (also known as the loading screen). They are the first three things a user will see when launching your app so they are important to have. The name will appear below the icon. The icon is the face of your app when users are browsing BlackBerry World or once downloaded in their grid of icons. The splash screen is the first thing shown when a user launches your app.
To change the name of your Cascades BB10 app (by default it will be the name of your project), edit the bar-descriptor.xml file. You either adjust it on Applications tab (see image below) or in the Source add the tag: <name>My App Name</name>
The default icon is a generic box icon and you would never want that. As for the splash screen, it is a dark gray background and says "BlackBerry" which looks something like this:
I see many apps use this and look fine. But its nice to greet your user with something unique. Or another good tactic is to have the splash screen the same background as your app's UI so it gives the illusion of your app loading faster than it does.
Just like the app name, these can also easily be changed in the bar-descriptor.xml file shown below:
Click on the "Application" tab (circled in green) then select an image for the icon (boxed in red) and splash screen image (boxed in blue). To select images click on the "add" button. In the popup you can either choose to select an image from your workspace (meaning it is in the project) or from the file system in your computer. Once you have selected the appropriate image(s) it will appear in the path/size list.
Or for the purist you can add code into the the Source tab of the bar-descriptor.xml file using <icon></icon> and <splashScreens></splashScreens> tags.
Icons should be 114x114 pixels for Z10, Q5, and Q10 and 94x94 pixels for Z30. Splash screens will be device dependent so I currently only have one loaded for the Z10 (1280x768). For splash screens to be loaded in portrait mode they should be 768 pixels wide by 1280 pixels tall. For splash screens to be loaded in landscape mode they should be 1280 pixels wide by 768 pixels tall. If I wanted different ones for the Q5/10, then I'd need add a 720x720 image. Similarly, for the Z30, a 1280x720 image.