(Image credit: TAG Heuer)

TAG Heuer was one of the first luxury brands to not only make a smartwatch, but make one running Google's Wear OS platform. Its first model was the TAG Heuer Connected, which was launched way back in 2015. But back then, not only was Wear OS great for Android device owners, it worked almost as well with iPhone.

And while Google didn't technically remove iPhone support in the interim, the new version of its smartwatch software made it harder for brands to implement. As 9to5Google points out, Samsung's latest smartwatches and Google's most recent Pixel Watch 4 don't work with iPhone, for example.

However, that's something TAG Heuer has corrected with its own software.

The TAG Heuer Connected Calibre E5 runs what the company calls "TAG Heuer OS" )(via Wired). And although it remains based on Android, it is not Wear OS.

(Image credit: Tag Heuer)

What does the Tag Heuer Connected Calibre E5 offer?

The listing for the new luxury smartwatch describes the OS as proprietary and with a user experience that has been "developed entirely in-house".

It also mentions dual-band GPS and the smartwatch's ability to monitor sleep patterns, heart rate variability and SpO2 levels.

It comes in a fine-brushed and polished steel case, and measures 45mm, with a black polished ceramic bezel. The watch is 14.8mm thick and water resistant up to 50-metres.

There are a number of customisable watch faces, which TAG Heuer says reflect the "iconic Carrera and Formula 1 collections", and the OLED display measures 1.39-inches with Sapphire Crystal protection. It provides a 454 x 454 pixel resolution.

By switching to its own operating system, the TAG Heuer Connected Calibre E5 also comes with a Made-for-iPhone (MFi) certification.

The smartwatch is available now and comes in four colour different options, with the cheapest starting at $1,700 / £1,350 / €1,550 and the most expensive Golf Edition setting you back $2,400 / £2,050 / €2,400.