If you use your Handheld PC on the go and are in education or engineering. Then quite possibly there are times when a more powerful on-device calculator would be useful.
Calculator.org, creators of Calc98 have an advanced engineering, fully customisable calculator available for Windows CE 2.00 and above devices.

The current release, Calc98 version 5.6 is currently under a special introductory offer for $9.85 USD (£5.50 GBP, €7.90 EUD, ¥1100 JPY est.) with a regular retail price of $23.95 USD. All the available Windows CE versions are included in the purchase licensing you to use Calc98 on any Windows CE 2.00 device up to the latest Handheld and Pocket PC devices. As well as a desktop Windows version.
A free download is available for version 5.3 for CE 2.00 and above.

View: Calculator.org