The original Touch launched as a competitor to the iPhone, but although the touch-interface was great for viewing photos and playing music it was a chore to send texts or make phone calls. That’s what the sliding keyboard of its follow-up – the Touch Dual – aims to redress.

It’s important to note there are two versions of the Touch Dual: there’s a 16-key model sporting a normal smartphone-like keypad with three letters per key and a 20-key version with a QWERTY keypad that has two letters per key. The latter is better for accurate text entry, but lacks the dedicated start, mail, web and back keys found on the 16-key devices.

As usual, HTC has provided enhancements, allowing more productive use of the touchscreen. In particular, there are options for launching programs, viewing and zooming images and navigating the contacts list. But when it comes to writing emails or sending texts, you’re still dumped into the usual Windows Mobile 6 apps. The new keyboard helps, and it’s quite an engineering feat to include it for just an additional 2mm of thickness, but it exposes the limitations of a device with interface tweaks layered over the top of something originally designed for stylus operation. The finger-based screen interface of the iPhone goes to the heart of the device’s design philosophy and is more successful as a result.

However, if you look past the Touch Dual’s image as a wannabe iPhone and think of it as a serious business tool, it starts to make a lot more sense.

It runs the Professional version of Windows Mobile 6, so it includes the full version of Office Mobile and it’s easy to add the Remote Desktop client. There’s no Wi-Fi but HSDPA means mobile data flies.

There’s no denying that the underlying awkwardness of Windows Mobile stops it from being a credible competitor to the (unavailable in Australia) iPhone, but the HTC Touch Dual is worthy of consideration in its own right. For business people in need of push email and Exchange integration, it offers a very sleek and sexy way of doing it.