Ovulation prediction and 86 decibels loud - This Apple Watch is full of tricks

Actually, large watches are no longer a rarity and should therefore not be particularly noticeable. This is different with the new Apple Watch Ultra. In the test, it happened to us several times that we were asked about it.

On the one hand, this is due to the size of the watch, which is 49 millimeters high and 44 millimeters wide, but also to the bright yellow strap to which our model was attached. Without wanting to evaluate it at this point: the watch is an eye-catcher. But of course not only that.

In the test, we only separated from the Apple Watch Ultra for a very short time over a period of more than a week to charge it in between. In addition to sleep tracking, there is a function that only works during sleep: measuring the temperature on the wrist.

This only happens every five seconds during sleep. To do this, however, the watch must first record a reference value, which only happens after five nights. The body temperature is not displayed in the Health app on the iPhone, but rather the deviation from the reference value.

The fluctuations that indicate a biphasic change in women are then interesting. Such a rise in temperature often occurs after ovulation. Users then get a notification on their Apple Watch about the probable day of ovulation.

Men, on the other hand, are allowed to interpret all sorts of things into their fluctuations: jet lag, alcohol consumption or a budding flu or corona infection. According to Apple, it wants to measure the temperatures very precisely.

There is a sensor for this on the underside of the watch right on the wrist and a sensor under the display to monitor the ambient temperature. We compared the temperature fluctuations with the measurements of the Oura ring and - without being able to identify the culprit - found that both devices fundamentally disagree.

But basically, the Apple Watch Ultra is not particularly suitable for wearing at night because of its large format - also not for wearers of long-sleeved shirts, because at 1.5 centimeters it is also rather clumsy.

But the watch makes a very stable impression. The case is made of hard titanium and encloses the screen's flat sapphire glass. Possible shocks mainly hit the case.

The rotating crown is also protected by the case. In addition, it is almost 30 percent larger than the – also new – Apple Watch Series 8. The crown can even be operated with gloves.

For the first time on an Apple Watch, there is another orange button on the left side of the watch that can be individually assigned with functions such as workout, compass, waypoint, flashlight or stopwatch.

Because Apple developed the Watch Ultra for extreme tough use: diving, mountaineering, water sports, triathlon. It works at temperatures between minus 20 and plus 55 degrees Celsius, is waterproof and, thanks to improved GPS with two frequency bands, uses satellite to locate its location even between urban canyons better than other watches.

Of course, the Apple Watch Ultra had to be upgraded a bit compared to other Apple watches. Three microphones with intelligent control now enable telephoning even in the wind, two loudspeakers make the conversation easier to understand.

They are also able to emit an extremely annoying siren and SOS sound of 86 decibels, for example to draw attention to injuries in unclear terrain.

In the test, the tones could still be heard at a distance of 150 meters. Apple even states a range of 180 meters. If you are right next to the clock, you won't be able to stand it for long.

In water, Apple Watch Ultra automatically displays the underwater time, depth, and water temperature in a depth app. This worked in the swimming pool at a depth of just ten centimetres.

Later this year, Apple, together with Huish Outdoors, will deliver an app called Oceanic, which turns the Apple Watch Ultra into a real diving computer that can be used to dive up to 40 meters deep.

However, the app will only be usable with a subscription. The watch is certified to EN 13319, an international standard for scuba diving accessories and depth gauges.

Of course, the watch also tracks many other sports. We've used them swimming, rowing, biking, running and on the elliptical. But the Apple Watches have also been very reliable here so far. We didn't notice a difference.

However, the display of the Apple Watch Ultra is twice as bright as the screens of the other Apple Watches. It is easy to read even in bright sunlight.

Of course, all the new features drain the battery. Apple has installed a 76 percent larger battery here, although the housing has only become about a third larger. Apple itself now specifies the runtime with normal use as up to 36 hours. In the test, that turned out to be an understatement. We could even use the watch for two days and two nights with just over an hour of sports tracking per day.

There is also a power-saving mode hidden in the settings, which is supposed to increase the runtime to up to 60 hours. But this only works with some restrictions.

So users then have to do without the always-on display and background activities such as automatic workout recording, heart rate and blood oxygen measurement. In addition, the cellular connection is restricted, so that notifications arrive with a delay.

Conclusion: For most smartwatch users, the Apple Watch Ultra is likely to be oversized. Anyone who only tracks their normal sport and is not out and about in extreme situations will also get along well with the new Apple Watch Series 8, which, however, then has to be charged more frequently.

But the Series 8, which does not look different from last year's model, comes with some new features of the Apple Watch Ultra, including temperature measurement and accident detection using improved sensors.

After a car accident, the watches then automatically call an emergency number and transmit the location. For many users, however, it should ultimately be a price and design decision.

The Apple Watch Ultra costs 999 euros with mobile reception, the Apple Watch Series 8 is available with mobile reception from 619 euros.

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