Samsung ​Galaxy Watch 4: Wear OS and big changes confirmed

Updated: Everything we know so far about the next Samsung smartwatch
​Galaxy Watch 4 rumor round-up
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The Samsung Galaxy Watch 4 has now been confirmed, and there are big changes ahead for the flagship smartwatch.

The rumors of the smartwatch moving from Tizen to Wear OS are true, and this was confirmed at the Google I/O conference in May. Wear OS and Tizen is officially a "unified" OS, but it seems that Wear is very much the technical base for the platform.

And while the Galaxy Watch Active 4 wasn't mentioned by name, rumors suggest this will also align with the flagship Galaxy Watch on the same platform.

Read on for all the information we have – and what's been rumored.

Update: This article was updated in June 2021 to include release date and sizing rumors.

Samsung Galaxy Watch 4 expected 28 June

Samsung Galaxy Watch 4/Active 4 release date

There’s no official word on when we’ll see the Galaxy Watch 4 or Active 4, but given the devices have already popped up at regulators, it could be soon.

Now that their existence has been confirmed, we were told by a Google spokesperson that there would be more news related to Wear OS at MWC 2021 in Barcelona. That is scheduled for 28 June - 1 July, which tallies with rumors suggesting the Galaxy Watch could be unveiled around that time.

And that's been backed up by an event listing on the MWC website.

There's an Customer Experience event scheduled for 28 June at MWC 2021 called “Galaxy Ecosystem / New Watch Experience / Mobile Security.”

Given the event is tagged “Customer Experience” it seems likely this event could follow a more formal unveiling in the preceding days. No press conference or Unpacked event has been announced as yet.

Samsung Galaxy Watch 4/Active 4 – Wear OS

Wear OS

The biggest news about the Samsung Galaxy Watch has already been confirmed – it will switch from Tizen to Wear OS.

Wear OS is to go under a major overhaul, and it's now a "unified OS" with Samsung and Google bringing tech to the party. That means it will enjoy some of the usability aspects and features of Tizen, but also the app catalogue of Wear OS.

Bringing Samsung's brand and volumes to the table – coupled with Fitbit running the fitness tracking – will certainly ignite interest in the platform, and this was made clear in a statement by Samsung.

"Behind every great user experience is a thriving developer ecosystem. With the new unified platform, we are unlocking a whole world of opportunities for the developer community. With a broad, open ecosystem, more developers and partners can apply their talents to work with us in evolving and redefining the smartwatch experience," read a post on the Samsung blog by Janghyun Yoon, EVP and Head of S/W Platform Team.

"Our hope is that this platform will ignite innovation in spaces like the Galaxy Watch Studio and inspire third party development, bringing a bigger and better network of apps to benefit Galaxy users around the world."

Samsung was a launch partner for Wear OS back in 2014, but switched to its own operating system for the Gear 2. It's spent the last 5 years growing a selection of apps, watch faces and features for Tizen, including top-end health metrics such as blood pressure, ECG and other apps such as hand washing timers.

Galaxy Watch 4/Active 4 Wear sizes and versions

Galaxy Watch 4/Active 4 versions

Evidence a new batch of smartwatches has materialised in the form of version numbers appearing at regulators.

That's according to the folks at Sammobile who've spotted that a batch of Samsung smartwatches have received certification at the CCC in China. When things start getting certified that's usually a good indication that we are not too far away from seeing them announced and launch

There are four models listed in total, with the SM-R860 and SM-R870 models said to be tied to the Samsung Galaxy Watch Active 4. The SM-R880 and SM-R890 numbers are said to be the ones related to the two versions of the Samsung Galaxy Watch 4.

In terms of sizes there have been rumors pointing to a size change. It seems likely the Galaxy Watch 4 will grow 1mm in both versions. While there have been rumors of 40mm and 42mm sizes for Active 4 – we just don't believe Samsung would ship two watches with such a minimal difference. We're more inclined to go with a different rumor from a Korean carrier database that points to 39mm and 43mm sizes.

We're expecting to see:

  • Galaxy Watch 4 42mm Bluetooth
  • Galaxy Watch 4 46mm Bluetooth
  • Galaxy Watch 4 42mm LTE
  • Galaxy Watch 4 46mm LTE
  • Galaxy Watch Active 4 39mm Bluetooth
  • Galaxy Watch Active 4 43mm Bluetooth
  • Galaxy Watch Active 4 39mm LTE
  • Galaxy Watch Active 4 43mm LTE

Samsung Galaxy Watch 4 battery sizes

A separate certification discovered suggests that the Galaxy Watch 4 will feature a 247mAh capacity battery and will support 5W charging.

In terms of when we can expect the Samsung Galaxy Watch 4 and the Galaxy Watch Active 4 to be announced, both are tipped to be unveiled around August this year. Samsung's Galaxy Watch does usually get announced around this time, so that seems like the most likely launch window. While the first Galaxy Watch Active first showed up in February 2019, its successor launched in August too.

So it looks like we might only have to wait a couple of months to see what Samsung has in store for us.

Galaxy Watch 4 features we want to see

Advanced fitness and guided workouts

Galaxy Watch 4 rumors: huge changes expected for Samsung

When the Samsung Galaxy Watch 3 landed it sought to offer more running appeal with new advanced running metrics that promised to track aspects of your form and technique without the need for an additional accessory to make it possible.

It's a feature powered by a company called Myotest, who we covered way back in 2017. Samsung recently rolled out an update to the Galaxy Watch Active 2 to add the same functionality.

Our experience on the Galaxy Watch 3 was mixed, though having only been available on the more expensive Samsung smartwatch, we'd anticipate that the company would look to roll out the advanced running metrics support to the next Watch Active and Galaxy Watch too and look to enhance the way it can explore how you run and not just how far or fast you run.

We might see Samsung also try to rival something like Apple Fitness+ for its Active 4 watch. The company has partnered up with wellness brands like Calm in the past – so it would make sense to do something similar with workouts.

Blood glucose tracking

Blood glucose tracking

Now this really could be a big one if the rumors around it ring true. Samsung has already joined Apple in offering an ECG sensor on its watches for medical grade-like heart rate monitoring and it's also added blood pressure monitoring support too.

The suggestions Samsung will offer the potentially groundbreaking feature comes courtesy of Chinese website ETnews who says the sensors have been developed in conjunction with MIT. The concept of being able to non-invasively track blood glucose would be a huge thing for diabetics and even serious athletes, so if Samsung has really pulled this off, it could well give its smartwatches a serious upper hand on the competition when it comes to monitoring your health.

However, a report by a Korean language site Money Today has ruled this out for the Galaxy Watch 4 – which seems like a safe bet.

Blood pressure and ECG for more smartphones

Blood pressure and ECG for more smartphones

Samsung has rolled out ECG and blood pressure monitoring apps for its smartwatches, but something that's not as well publicised is that it only works with Samsung smartphones. That means that users of other Android handsets are locked out.

This begs an interesting question: will a move to Wear OS make Samsung's health features more accessible?

It would seem bizarre to move to the more open platform of Wear OS but still keep some features locked into the Samsung ecosystem. Here's hoping.