Let’s get this out of the way: Yes, a smartwatch can save your life. We need to be more specific for the question to be meaningful. Some years ago, the iPhone saved a man’s life just by being in his shirt pocket. He was shot. But the bullet struck the iPhone and did not penetrate the casing. Life saved. Of course that is not what we mean.

Apple just recently upgraded the Apple Watch to Series 6. The company is very proud of the wearable’s life-saving capabilities. Some have criticized Apple for the boast. Are those critics just anti-Apple trolls who are jealous of the number 1 watchmaker in the world? Or is there reason to be skeptical of the implied claims? As with many things, the truth might lie somewhere in the middle. Here is a closer look a what a smartwatch can and can’t do with regard to saving lives:

It Can’t Detect Depression and Other Mental Illnesses

Prior to the release of the Series 6, there were rumors that the Apple Watch would be able to detect emotional variance. This has also been rumored for ear buds, smart speakers, smart rings (think digital mood ring, and every other device. Whether or not such is even possible, you can be sure that there is no such feature in any shipping smartwatch.

If you suffer from depression, don’t look to smartwatches for treatment. Look to medical technologies like Transcranial Magnetic Stimulation (TMS). What is TMS for depression? It is not a consumer wearable or a pie in the sky sci-fi/fantasy trope. It is a non-invasive procedure done without the need for anesthesia of any kind that has a proven track record of bringing about remission in depression sufferers. See your doctor to find out if it is right for you. Don’t rely on your smartwatch for anything other than keeping you on time for your appointment.

It Can Help You Survive a Fall

For two years, the Apple Watch has had the ability to detect if the wearer has fallen and automatically call emergency services for help. In the process, it also notifies that person’s emergency contacts. It is a feature that genuinely can, and repeatedly has saved countless lives.

From Dick Tracy to modern healthcare, smartwatches have leapt from the pages of comic books to life-saving devices in the real world. Just be aware that not all smartwatches are created equally. Don’t expect the same functionality from the $200 discount knock-off.

For a feature like this to work well, the watch has to have a high-quality, finely calibrated motion detector, the ability to make calls to emergency services from just about anywhere, and access to your contacts. Apple Watch sits at the top of the price chart for a reason. Check features and reviews before trusting your parent’s life to a smartwatch for fall detection. This is not the place where you want to cut cost.

ECG: Yes and No

The Apple Watch is no longer the only smartwatch that can take a single-lead ECG. However, it has been more rigorously tested in the real world by real people who have benefited from the technology.

It does not diagnose heart attacks. If you are having symptoms of a heart attack, get to the ER right away. Do not stop to consult your smartwatch. It simply doesn’t matter what the smartwatch shows.

That said, the Apple Watch has a very good track record of alerting people to irregular heartbeats. It is a test and no because smartwatches can definitely do a version of an ECG. How useful that information varies by product. And they cannot tell you as much as a diagnostic ECG at a hospital.

No smartwatch should be used to take the place of a professional medical opinion. They are no good for detecting depression. They can be very good at detecting falls. And detecting heart conditions is a mixed bag. If you only care about telling time, any smartwatch will do. If you want to potentially save the life of yourself or someone you love, go for the best and not the cheapest.