(Pocket-lint) - The HTC smartwatch has been often rumoured, but has failed to appear, with dates in 2015 and 2016 slipping by, with HTC staying out of the smartwatch arena.

HTC does have some wearable devices however, first showing off the HTC Grip, a sports device that was first revealed as a prototype alongside the HTC One M9 in 2015 and fruit of the early Under Armour union. The Grip slipped and we were given the UA Health Box instead, including the UA Band, in early 2016.

But a dedicated smartwatch remains elusive. First called Petra, then dubbed the One Wear, recent leaks have carried the HTC Halfbeak name. Sadly, it seems as though this was nothing more than a prototype, for a project that's not going to be released. Here's how the story unfolded, and how it finished.

Round display

Heart rate sensor

UA branding

At the end of 2015, the Halfbeak rumours appeared. These referred to a round smartwatch but it wasn't until October 2016 that a physical device appeared on Weibo. The telling thing about this device is the UA logo, lining this up as a watch coming from HTC's partnership with Under Armour. A second leak brings this device back into focus again showing off the lines of what looks like an UA sports watch, again pictured on Weibo.

The HTC Halfbeak has a round watch design with two buttons on the right-hand side, likely to be a home button for Android Wear and a second for a dedicated function, like start stop perhaps, or to launch a dedicated UA Record app.

The size is difficult to judge, but it looks similar to devices like Samsung Gear S3 or Moto 360, so we'd guess it's about 42mm in diameter across that display.

It's difficult to judge the materials, but the backplate looks plastic. The watch body is likely to be metal and it looks a little like the Samsung Gear S2: it could be metal, but the shiny finish on the bezel looks odd, and we doubt it will launch like that.

What we can't discerned is any level of waterproofing. Any sports device is likely to launch with an IP rating to let you swim or run in the rain, but there's no word on that. However there is an optical heart rate sensor on the rear of the watch.

The strap looks fairly conventional, with a two-tone silicone construction. It looks removable, but doesn't show signs of being easy to change from what we've seen.

Round display with no flat tyre

360 x 360 pixel resolution

Likely Qualcomm Snapdragon Wear

Attachable charging plate

The original leak of Halfbeak was rumoured to offer a 360 x 360 round display. That's fairly typical of this type of watch, but actual specs are very thin on the ground. One thing we can judge from the photos is that it's proper round, unlike the Moto 360 and others that have a flat tyre design, with a section at the bottom that's a black bar.

There's no word on specs, but there are a few options. HTC has a long-standing relationship with Qualcomm, so a Snapdragon Wear chipset is a possibility. The current norm is 512MB RAM and 4GB storage for an Android Wear device.

There is an alternative, however, and that's Intel. We've seen companies like Tag Heuer pair up with Intel to power devices. Currently, there's no way of knowing. There's also no way of knowing if there's GPS onboard.

What we have seen from the leaked images, however, is a snap-on charging plate. We don't know if it's magnetic or clipped, but it charges through the contact points on the rear. This does suggest that the device is waterproofed, as it avoids the need to plug anything in.

Android Wear platform

Likely to run UA Connect app

The leaks for Halfbeak clearly show that this is an Android Wear smartwatch. It makes sense to use an established platform rather than for HTC to go it alone.

We'd expect the focus to be on a UA Record app, although Under Armour also owns Map My Fitness (and associated apps), MyFitnessPal and Endomondo, all of which could be included.

With Under Armour branding, the company is likely to push its fitness apps and service first, rather like the Polar M600. This will likely include watchfaces with complications to show you things like steps and let you instantly access the sports app.

The HTC Petra device was the subject of rumours for some time. It was thought that the Petra would be announced at MWC in 2015 as "the official companion to the HTC One M9". Several reports claimed the device would go on sale during the first quarter of 2015 but that was clearly not the case - and could have been the Grip or UA Band that eventually launched.

The HTC Halfbeak was rumoured to be coming on 29 September 2015, again nothing appeared, even though the Halfbeak sounded more smartwatch than fitness tracker by this point. Serial leakster Evan Blass claimed a mid-April 2016 date, then said it had been pushed back till June, and still no launch.

As we sail into 2017, the Halfbeak appeared again, but plans for an Android smartwatch were definitively closed in an interview. Tbreak.com, talking to Chialin Chang, HTC president of smartphones and connected devices, said: "I can tell you that we're not going to have an Android watch. I don't think we've nailed it with watches. Android watch is one thing but even Apple as a big brand is declining. We are not going to have a watch in the short term."

That, as they say, is that then.

Writing by Chris Hall and Britta O'Boyle.