These actions will only work on I-Series device that are unlocked.

Choose to Modify the button and then OpenApplication(appNameString) and when the Application picker opens select one of the available apps listed or select Installed Apps and browse to the executable file for the program/app you want to open.
If using OpenApplicationWeb(urlStr) type in the URL enclosed in quotes when the Expression Editor opens.
For OpenApplicationMaps(searchStr) type in an address enclosed in quotes when the Expression Editor opens.
To use OpenDocument(urlStr) browse to the document you wish to open.
OpenApplicationEmail() currently will not work because there isn’t a default email client installed. If you install an email client on the device then this action should work.