Cybex Sirona S I-Size car seat with SensorSafe review

Cybex’s new car seat accessory tells you when your child is trying to escape, is too hot, or has been left in the car

T3 Platinum Award
Cybex Sirona S I-Size car seat with SensorSafe review
T3 Verdict

We love the intelligent design features and soft memory-foam-style padding. SensorSafe is an innovate and potentially lifesaving piece of technology. It certainly gives a little extra peace to mind when using it.

Reasons to buy
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    Potentially lifesaving notifications

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    Easy to install

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    0-4 age range

Reasons to avoid
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    Notifications could be missed or distracting

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Whether you’re about to become a parent, have just become a parent, or are a seasoned pro at parenting, you’ll know exactly how important car safety is when travelling with a little one.

Yep, driving around with your precious cargo is equal parts exciting as it is nerve-wracking, so you’ll want a car seat which makes these journeys as stress-free as possible.

Enter SensorSafe, a brand new, innovative piece of technology from Cybex designed to improve the safety of your car seat and give peace of mind.

What is SensorSafe?

SensorSafe is a clip that attaches to the harness system of your Cybex car seat. It connects to your smartphone via Bluetooth, and provides important health and safety alerts.

For example, you’ll get an alert if your child unbuckles the clip, when the ambient temperature around your child is too hot or too cold, if your little one is left unattended in the car and if your child has been seated for too long.

Cybex Sirona S I-Size + SensorSafe review: Installation

We’ve been reviewing SensorSafe with the Cybex Sirona S I-Size car seat. When you first install the app, it’ll guide you through the installation of SensorSafe in your car, then the installation of the car seat.

It gives you a really simple to understand guide, with clear information on all of the safety features.

The Sirona S is ISOFIX, so installation is incredibly easy. 

Having this clear information does make installing the car seat less stressful, however, with additional information about how to make adjustments to the seat as your child grows. This is especially useful for first time parents.

Cybex Sirona S I-Size + SensorSafe review: Comfort and features

The build quality of the Sirona S I-Size is exceptional and we love the fact you can use it from birth to approximately 4-years-old. It looks great, and the seat features plenty of memory-foam-like padding, which got a lot of compliments from our little tester. 

It also feels incredibly well made, and is easy to use once you get the hang of everything. Installation was straight forward, as was getting a child in and out, thanks to the rotating seat. 

Cybex Sirona S I-Size + SensorSafe review: Harness alerts

The real star of the show here is the SensorSafe alerts. Cybex states 51-percent of parents have reported that their child has unbuckled themselves from their car seat, so this is clearly a wide-spread problem.

SensorSafe combats this in two ways; first by making the clip more secure, therefore harder for your child to open; secondly by sending a push notification to your smartphone if your child does manage to escape, at which point you can stop the vehicle and strap them back in.

Of course, this does mean your phone will need its volume turned up, or be connected to your car. Otherwise, you’ll miss the notification.

That’s not all SensorSafe will notify you of, though, as it also measures how long your child has been clipped into the seat (and will recommend when to take a break), and will also send you a notification if the driver leaves the car with the child still buckled inside (if nothing changes after five minutes the app can send notifications to your emergency contacts letting them know the child has been left in the car, along with the car’s location.

And finally, SensorSafe contains a thermometer, and will send you a warning when the temperature in your car reaches either 35°c or falls to 7°c. This will help prevent your child from overheating or get too cold whilst in the car.

Cybex Sirona S I-Size + SensorSafe review: Availability

SensorSafe is not sold as an accessory, instead, it has to be chosen as an option on certain Cybex car seats.

It comes on the Platinum Cloud Z and Sirona Z, as well as the Gold Aton M i-Size, Sirona S i-Size, and Sirona M2 i-Size.

Cybex Sirona S I-Size + SensorSafe review: Verdict

The Sirona S i-Size car seat from Cybex offers seriously comfortable rear and forward-facing travel for children up to 105 cm. We love the intelligent design features and soft memory-foam-style padding which resulted in lots of compliments during our review period. 

SensorSafe is an innovate and potentially lifesaving piece of technology, which we found very easy to use. Phone notifications do take your eyes off the road, which could cause issues, however, if used sensibly, we found SensorSafe certainly gives a little extra peace to mind when using it. 

Spencer Hart
Style and Travel Editor

As the Style and Travel Editor at T3, Spencer covers everything from clothes to cars and watches to hotels. Everything that's cool, stylish, and interesting, basically. He's been a part of T3 for over seven years, and in that time covered every industry event known to man, from CES and MWC to the Geneva Motorshow and Baselworld. When he's driving up and down the country in search of the greatest driving roads, he can be found messing around on an electric scooter, playing with luxury watches, or testing the latest fragrances.