The HTC Universal is a GSM/GPRS/3G/Wi-Fi Pocket PC, while the HTC Apache is a CDMA/EV-DO/Wi-Fi Pocket PC. They are both running Windows Mobile 5, while the HTC Harrier is a Windows Mobile 2003 CDMA EV-DO Pocket PC.
Check the pictures, and soon I will be posting individual reviews:
It seems strange, but the HTC Apache, with a slower (416MHz) CPU seems faster than the HTC Universal with a faster CPU (520MHz). The HTC Universal comes with live video calling when used on a 3G (UMTS) network (such as the Vodafone NZ 3G), while the HTC Apache has a faster (CDMA EV-DO) 3G connection.
Also, the HTC Apache is much smaller and lighter than the HTC Universal, and looks more hip.