The combination of price and accuracy makes the 4iii Viiiiva one of the best heart rate monitors out there, and it goes beyond the smart bridging feature, which transmits ANT+ signals from other devices via a Bluetooth connection.
While its battery life is lower compared to newer devices, the 4iiii Viiiiva is still worth considering as one of the best cheap heart rate monitors out there, even if you don’t need the bridging feature.
4iiii Viiiiva Heart Rate: Price and Availability
The 4iiii Viiiiva was originally released in 2012 and it’s a testament to the quality of the display that you can still buy it today. The price has dropped in the meantime and the 4iiii Viiiiva’s list price is now $49.99/£49.99.
How I tested this heart rate monitor
I’ve been wearing the 4iiii Viiiiva to track my workouts for several weeks now, either on its own or paired with the Polar H10 chest strap to test the Viiiiva’s accuracy. I’ve used it mostly for running, along with a few strength sessions.
Plan
The 4iiii Viiiiva is a lightweight sensor with a plastic main unit that clips onto an adjustable fabric strap, with the lobe acting as a strap buckle. The sensor uses a CR2032 battery and connects to other devices via Bluetooth and ANT+. It can only support one Bluetooth connection at a time, while many heart rate straps can now support two or three.
Once the sensor snaps into place, it’s easy to pair it with another device, although you don’t get any beeps or lights from the pod itself to indicate it’s connected. The strap is adjustable from 23 inches to 52 inches (57-132 cm) and I’ve found that once I’ve set the desired length it stays in place reliably and comfortably during long workouts.
Viiiiva has an IPX7 waterproof rating and can be used to monitor your heart rate while swimming, as it is waterproof to depths of 3 meters and can store workout data on its internal memory for later download.
The internal storage can record up to 65 hours of heart rate data in .fit files that you can download from the partner app. If you connect other sensors such as power meters to the Viiiiva, it will also record this data (although this reduces the number of hours it can store), making it a handy backup in case the clock or bike computer you get stuck or run out of battery during a workout.
Sports performance
For all its clever tricks, the 4iii Viiiiva wouldn’t be much use if it weren’t an accurate heart rate monitor, so I’m happy to report that it performed flawlessly throughout my testing. It reliably recorded the same heart rate as the Polar H10, which I found to be the most accurate HRM available through years of testing.
I did several hard runs wearing both the 4iiii Viiiiva and the Polar H10 connected to different watches. Both during the sessions and when looking at the heart rate graph afterwards, I saw no differences in the readings of the two HRMs.
During the weeks I used the 4iiii Viiiiva I was able to connect it to a variety of watches and apps with ease, although the fact that it only connects to one Bluetooth device at a time meant I had to disconnect it from one to connect it to the another. It also means that if you use Viiiiva with a Bluetooth-only sports watch and Zwift on a Bluetooth-only device at the same time, only the watch or Zwift can show your heart rate.
ANT+ bridging function
While ANT+ bridging isn’t a feature I need, it’s something that will be invaluable to some and is the main reason to choose the 4iiii Viiiiva over other heart rate monitors.
To use the feature, connect the 4iii Viiiiva to the partner app, connect your ANT+ devices to the heart rate monitor there, then stream to an external device.
When the 4iiii Viiiiva was first released, its ability to connect ANT+ devices to Bluetooth devices was much greater. Since then, Bluetooth connectivity has become a standard feature in sports sensors.
However, bridging still has its uses, especially for anyone with an older ANT+-only indoor bike sensor or trainer. Another use of the bridging feature is that it can group multiple ANT+ signals into one Bluetooth signal, which is useful when connecting to Zwift or other apps on a device that can only handle two Bluetooth signals, such as the Apple TV.
Battery life
4iiii says the Viiiiva will last up to 160 hours on a single battery, which is significantly less than most HRMs that use coin batteries. The Polar H10 lasts 400 hours on a coin battery, for example, and the Wahoo TICKR lasts 500.
I found the battery drained faster than that 160 hour estimate. You can see your device’s battery life in the partner app and mine has dropped to 64% after about 30-40 hours of use.
Is 4iiii Viiiiva worth it?
The 4iiii Viiiiva is an accurate heart rate monitor at a great price and if you use bridging, buy it. If not, you can get accurate heart rate monitors for less, like the Coospo H9Z, which has a rechargeable battery and can handle two Bluetooth connections at once, though it can’t store workouts or track swimming.
If you upgrade to more expensive models like the Polar H10 and Garmin HRM-Pro Plus, you’ll get longer battery life and more comfortable straps and some extra features like technical running stats on Garmin, but you don’t get a more expensive device for your money.
