The original HTC Touch Diamond was the product that introduced the company's fancy TouchFlo 3D interface to the world. This was a more advanced version of its first TouchFlo interface and subsequently made appearances in other products like the Touch Pro and Touch HD. It's fitting then that the latest version of TouchFlo 3D should debut in the Touch Diamond2. This new smartphone's updated interface is by far its strongest feature--we tell you why.

Design

A quick glance at the Diamond2 reveals that it shares the same DNA as the original. Its shape can be described as lanky, with a footprint of 107.9 x 53.1mm. Though it doesn't retain the prism motif on the back like the Diamond, the Diamond2 is thicker at 13.7mm, up from 11.3mm. While most of this new handheld is black in color, its sides and front button area come in a silver brushed-metal finish. If you liked the look and feel of the original Diamond, chances are you will like this one, too. The downside is that the same tendency to attract fingerprints on the back has also been inherited.

The back of the Diamond2 doesn't come with the prism motif.
(Click for larger image)

Buttons have been kept to a minimum, with four on the front, a power button on the top and volume control on the left side. In keeping with the requirement from Microsoft for a future Windows Mobile 6.5 (WM6.5) upgrade, one of the front buttons has the Windows logo and brings up the Start menu when pressed. The Diamond2's stylus is found on the bottom right corner and, like its predecessor, causes the screen to turn on when pulled out.

The touch-sensitive display on the Diamond2 measures 3.2 inches diagonally and has a WVGA (800 x 480) screen resolution. Comparing this with other WM phones sporting WVGA screens shows that the Diamond2 is a touch larger than the 3-inch display on the Sony Ericsson Xperia X1 but smaller than the massive 3.8-inch panel on the HTC Touch HD. One of the potential problems of having so many pixels packed in a small device is with reading text. While the pixel density allows for sharp images, letters and words can sometimes be too small for comfort. This issue is addressed by a zoom bar found right below the screen. In the browser and maps application, this zooms in to Web pages and maps, while in a text or email message, it lets you change the text size quickly.

Instead of a 4GB built-in storage like the original, the Diamond2 comes with a microSD card slot. This is found under the battery cover on the right side of the device. HTC does not provide a microSD card with the standard package but that's not a big deal considering how cheap this category of storage media is these days.

Like almost every other HTC smartphone, the Diamond2 has a single mini-USB port for charging, syncing and connecting a wired headset. This means an adapter is needed if you want to use your favorite 3.5mm audio headphones for music, an optional accessory that doesn't come with the device. One thing that does come bundled is a slim slip case with a leathery texture.

Features

On the surface, the wireless specifications of the Diamond2 don't differ much from the first iteration. Like the Diamond, it supports HSDPA and has Wi-Fi, Bluetooth and GPS for navigation. But there are improvements. For one, it comes with HSUPA for faster uploads over the cellular network. Also, the GSM radio is now a quad-band version instead of tri-band.

The physical changes may not be incredibly significant but the software enhancements are. A new version of TouchFlo 3D, HTC's package of OS tweaks meant to make the WM-based device more user-friendly, is found in the Diamond2. The Home screen looks basically the same, displaying a large digital clock by default and having tabs at the bottom which let you navigate to other screens showing items like your emails, text messages and music.

What's changed are the improvements made to the contact list. Instead of just being a means of seeing the contact details when you pick a name, tabs at the bottom of the panel let you see all interactions with the contact including text messages, emails and call logs. HTC has also improved the context menus by making them larger for fingertip operation. This works at the OS level so all third-party applications benefit from this, not just the HTC ones. The Start menu has also been changed, and you can no longer access the regular programs page. The new one has large icons not unlike what you see in Palm OS and OS X on the iPhone. Read more about this new TouchFlo interface together with some screenshots in our earlier preview story.

The browser has become an integral part of any mobile phone and HTC has been employing Opera Mobile in its devices for some time now. While this is the same for the Diamond2, what's different is that this application is found in the firmware. It's constantly resident in the memory and launches instantly whenever you need it. Rendering of pages has also been greatly improved and in our test we found the browser to be on par in speed compared with the iPhone. While we can't say our test was absolutely scientific, we did make sure that both devices were on the same data plan from the same operator and that all pages tested were never accessed previously to avoid discrepancies that may arise because of the browser's cache.

Implanting the browser into the ROM was a good move and we dare say the Diamond2 currently gives the best Web browsing experience for any Windows Mobile phone. Of course, this is possible only because HTC gave this smartphone a massive 288MB of RAM, up from the Diamond's 192MB. One gripe we have is the fact that the operator Home page is fixed so your operator logo will always appear on the Internet page in TouchFlo 3D when you use the Connection Wizard to implement your network settings. To work around this, we skipped the Wizard and keyed in our operator settings manually.

Text input has been slightly tweaked and comes with more virtual buttons because of the increased screen length. Tapping on each button will cause the phone to vibrate slightly so you know you hit it successfully. Like on the iPhone, each letter will also expand so you can visually confirm that you've pressed the correct one.

The 5-megapixel camera on the Diamond2 takes pretty good pictures. Colors turned out accurately and details were pretty good for a mobile phone camera. One useful feature is the ability to pick a focus point by tapping on the screen. This lets you frame your shot without always having the subject in the middle.

Performance

HTC claimed that the Diamond2 has 50 percent better battery life than its predecessor. In our tests, we got the same sub-two day use from a single full charge. But it's necessary to qualify that, because of the much improved browser experience, we surfed using HSDPA and Wi-Fi a lot more on the Diamond2, as much as 2 full hours spread over about 10 occasions in those two days. If you make lots of phone calls over a day, it's very likely daily charging will be required. We are pretty sure the battery efficiency is better than the original Diamond as reviewed by us in the middle of 2008. But as to whether it's a full 50 percent more, we are not so sure.

The new TouchFlo 3D was very efficiently implemented and we hardly felt any lags in our period of use. You would expect the increased screen resolution to slow down the device because more pixels have to be drawn at any one time, but we didn't experience that at all, thanks probably to the large amount of onboard RAM.

Voice quality was excellent and video calls were good as the speakerphone was quite loud. We also had no problem with the GPS, but take note--HTC will not be bundling any GPS software that does turn-by-turn navigation, so factor that into the cost if you need one.

Conclusion

Ironically, the best Windows Mobile phones are the ones that don't look like they use Windows Mobile. That, essentially, is what HTC has managed to achieve with the Touch Diamond2. The new TouchFlo 3D is by far the best manufacturer-bundled custom interface we have used. Some advanced users may prefer certain third-party ones, but out-of-the-box, we believe many will be entirely satisfied with the Diamond2's interface.

At S$1,088, the Diamond2 is pretty expensive. That's the price without subsidies, and if past phones are any indication, you will likely pay anything from S$400 to S$800 for a set if bundled with an operator contract. For comparison's sake, an unlocked 8GB iPhone bought directly from the Hong Kong Apple store costs S$1,048. The Asus P835 with almost identical specifications (but which is slightly larger and heavier) is more affordable at S$798.

Aside from price, our other reservation is the lack of a dedicated 3.5mm audio jack. That said, HTC positions this smartphone as a stylish yet powerful device, and not for multimedia performance like the Touch HD which does come with the said audio port.

All in all, the strengths of the Diamond2 greatly outweigh its weaknesses. The performance issues we had with the Touch Diamond that prevented it from getting our Editors' Choice award have been addressed here.If those have been plaguing you, this new version is a worthy upgrade. Furthermore, HTC will be providing a free upgrade to WM6.5 when that becomes available, so this smartphone is pretty future-proof in terms of software.

If you are in the market right now for a good-looking, compact WM phone with a truckload of features, and are able to get a good discount from your operator, the user-friendly HTC Touch Diamond2 will be your best bet.