At HTC's London event on Wednesday, they company showed off two things. As expected, there were a couple of handsets: the Desire HD and Desire Z. But what HTC opened with was not handsets, but a new website—htcsense.com—and its accompanying phone front-end.

The phones were nice enough. The Desire HD is a GSM/UMTS/HSPA equivalent to the EVO 4G available in the US exclusively on Sprint; the Desire Z is slightly lower-specced than the HD, but will likely gain wide appeal as it has a hardware keyboard. The Desire Z will form the basis of the forthcoming T-Mobile G2 in the US, the spiritual successor to the G1 (which was, back in 2008, the first Android handset to ship). T-Mobile's version will include a different radio (to support T-Mobile's awkward 1700 MHz frequency allocation), and more excitingly, will support HSPA+, the next generation HSPA technology that ultimately provides data rates up to 56Mbps downstream, 22 Mbps upstream.

HTC Sense... makes sense

But the hardware wasn't really the point of the event. What the company was more excited about, and spent most of the time on-stage talking about, was software and web services. Specifically, HTC's Sense software and the company's new HTCSense.com web services (though the site isn't actually accessible at present, as it's still in development). Even the operating system of the two phones—Android 2.2—barely got a mention.

HTC has long had custom front-ends on its smartphones. In the olden days of Window Mobile, it was largely to make up for user interface atrocities that operating system inflicted on users; TouchFlo and derivatives provided a shell that was at least somewhat finger-friendly, even if the rest of the operating system was stylus-driven. The latest incarnation, Sense, is a little different. The Sense customizations on the latest Android handsets are no mere thin veneer over operating system functionality. Rather, they are replacements for many of the Google-developed applications that typically ship with Android handsets.

For example, HTC has a new maps application that replaces Google Maps. It includes turn-by-turn and other expected features, but also includes some new, HTC-specific features. It allows maps to be precached, so that when abroad, say, you don't need to use expensive roaming data to pull down map information—you can load the maps you need at home, or using your hotel's WiFi, and then just stick with the cached data. HTC also showed off dialer integration; if you get a call when using turn-by-turn navigation, the dialer doesn't cover up the map software. Instead, it makes the map view slightly smaller, and allows the call to be answered from within the map application. The idea is to ensure that you don't miss a turn just because someone calls.

The online capabilities were not ground-breaking, but welcome nonetheless. Text message backup, photo backup, and lost phone functionality were all included in HTCSense.com. In contrast with Apple's similar MobileMe offering, but in keeping with Microsoft's equivalent MyPhone service, HTC said that HTCSense.com would be free for anyone with a Desire HD or Desire Z. There was an implication that map data would be billed, however.

Attendees at the event didn't get much time to use HTCSense.com; the site isn't up and running, and so the handsets that were available to use couldn't access it. There were a few PCs available showing a prerelease version, and it appeared to work pretty much as expected. It offers the usual range of features: tell me where the phone is, ring it even if set to silent, wipe everything on the handset, as well as data syncing. Though slightly surprising that HTC wanted to tell the world about its online services without having even a placeholder site up, I'm sure that by the time the hardware launches—mid-October for the Desire HD, a little later for the Desire Z—everything will be working properly.

HTCSense.com was supported in both the handsets shown off, and is likely to be supported on future handsets using Sense. HTC was noncommittal when asked if it would bring the features to existing handsets. Company representatives said that the HTCSense.com integration was dependent on having the latest version of the Sense software, which in turn requires Android 2.2. This would obviously be a stumbling block for handsets that don't run Android 2.2 (such as the venerable G1), but it's less clear why this should be a stumbling block for, say, the Desire HD's close sibling, the EVO 4G.

It's an HTC phone, not a Google phone

The representatives were, surprisingly reticent about Android. Yes, these phones did run Android, but they weren't "Google Phones." The look and feel was all HTC, the online value-add was all HTC, and though I wasn't timing the presentation, I think even Windows Phone 7 got more stage time than Android or Google did. The company emphasized that Sense was no mere skin for the OS, but a complete online and off-line software stack.

In doing this, HTC is taking steps down the same path as Chinese manufacturer OPhone. OPhone is using the open-source parts of Android—the GPLed kernel and the Apache-licensed middleware—but not Google's paid value-add applications: Mail, Maps, and most importantly Market. I don't know if the new devices still provide the Google applications (I didn't see an icon for Google Maps in my time with them, but it's possible I overlooked it), but plainly HTC isn't far from having total replacements for everything except for Market itself.

Android is designed to allow this kind of replacement, so it's not surprising. Such replacements form a core part of manufacturers' ability to differentiate their products from each other. HTC, naturally, wants people to demand HTC phones, not merely "Android" phones, and adding unique software features is the way the company has chosen to do that.

With the new Sense, HTC is just going further than most (other than OPhone, obviously), but where HTC follows, Samsung, Sony Ericsson, and others, are likely to follow, and for much the same reason as HTC: they don't want their handsets to be interchangeable with any other Android handset, they want specific features that will draw customers to their phones in preference to anyone else's.

After all, if it's worth it for HTC to spend time and money developing replacement software in preference to licensing Google's offerings, that's likely to be true for other manufacturers too. They're already taking steps in this direction (Samsung with its TouchWiz, Sony Ericsson's UX), and if HTC's move pays off, equivalent efforts will be the logical response.

The result of this could well be a marginalization of Google. Not overnight—companies like HTC still work closely with the advertising giant—but as the custom software matures, and vendors want to better distinguish their products, it seems likely. If the smartphone vendors are all writing their own software atop the free Android middleware, and eschewing Google's paid applications, the result could be that there's not much Google left. The Android strategy—give away the base operating system, but charge for the important user software that makes the OS useful—makes less sense if everyone writes their own user software anyway.

You can't do that with Windows Phone 7

This makes an interesting contrast with Windows Phone 7. Though HTC representatives wouldn't confirm any specifics about the company's plans for the platform, they expressed considerable excitement about it, along with some degree of optimism; they feel that the operating system works well and has much to offer users, albeit with concern that unless people actually try out the interface, it may be difficult to promote. Windows Phone 7 takes a different tack to Android and iOS, and while it's pleasant and coherent in use, it will nonetheless feel very different for users more familiar with those platforms.

Windows Phone 7, unlike Android, all but eliminates customization by manufacturers. There are a few areas that they can modify—camera controls are hardware manufacturer-specific, for example—but most of their custom features are "regular applications," just the same as third parties can write. Wholesale shell replacements aren't allowed.

HTC still believes that it can do enough with Windows Phone 7 to ensure that HTC's handsets are uniquely appealing to customers. Two leaked videos purportedly of HTC's Windows Phone 7 software show off the kind of thing that the company may be doing—but they also show off how little the company can do. Weather, stock tickers, and notes, but that's all: the home screen still looks like plain Windows Phone 7, features like e-mail, music, and text messaging all look like plain Windows Phone 7, and that's because they are. Nobody's allowed to change them.

Nor does it look like HTC be able to offer HTCSense.com-like features for Microsoft's platform; Microsoft itself will be offering this kind of functionality (though the details will differ), eliminating another avenue for product differentiation.

The result is that regardless of manufacturer, all Windows Phone handsets will be Windows Phone handsets first and foremost—not HTC or LG or Dell or Asus-Garmin. In terms of the value they offer to the hardware companies, the two platforms are diametrically opposed. Where Google is at risk of being made invisible on Android phones, the hardware companies have a similarly low profile on Windows Phone 7 devices.

Google may be comfortable with this—though it represents a potential loss of revenue, the company's main purpose is to sell adverts, so as long as Android phones have free and unfettered access to the web, Mountain View should be happy. The hardware companies win—free access to a decent middleware platform—and though Google won't exactly be winning too, it won't be losing. Besides, there's always revenue from the Android Market.

But for Windows Phone 7, the situation is less clear cut. In the face of a competitor that handset companies can make unambiguously their own, there may not be much desire to develop and promote a platform that renders the choice of manufacturer all but irrelevant: a platform where every phone is going to be unambiguously Microsoft.