Option 1: Remove the Software Using the Windows Mobile Utility
We've installed the trial of XCPUScalar on our Dell Axim, but we've decided not to invest in the full version and want to remove the trial from the handheld. Not being near our computer, we'll have to use the Pocket PC to remove the software.
To begin, use your stylus and tap Start > Settings > System (TAB). Locate and tap the Remove Programs icon:

In the Remove Programs utility, you'll see a list of user-installed software titles. Select and tap the software title you wish to remove (which in our case is XCPUScalar), then tap remove:

That's it. The application has now been removed from the mobile device. If you want to reinstall it, you'll have to use ActiveSync on your PC.
Option 2: Remove the Software Using ActiveSync
Removing Windows Mobile software with ActiveSync is as painless as using the built-in Remove Programs utility on your Pocket PC. To begin, connect your Pocket PC to your Windows PC and allow the sync process to complete. In ActiveSync, click Tools > Add/Remove Programs:

Here you will see a list of software titles you've installed on the Pocket PC. Find the title you'd like to remove from the handheld, uncheck the box, and click OK:

The software has now been removed from your Windows Mobile handheld, but the installation files remain on your Windows PC. If you would like to reinstall at some point in the future, simply return to the Add/Remove Programs utility, re-check the box to the left of the title, and click OK. If you want to remove the installation files from your Windows PC, you'll need to use the Add/Remove Programs utility built into Windows, which can be found in the Control Panel.
Final Thoughts
Because your Pocket PC's internal memory is limited, it's very useful to install software directly to your CompactFlash or Secure Digital memory card. These cards are very inexpensive and offer limitless software and file storage. Check this tutorial to see how to install software directly to a CF or SD memory card.