"SOS is a valuable feature and I'm surprised others didn't add it to their smartwatches before this," said Patrick Moorhead, an analyst at Moor Insights & Strategy.
"I think Apple's SOS is important as it could open up Watch to children and the elderly," he added. "It won't be long until we hear stories of people being saved by SOS."
Moorhead said SOS could be an important addition to Apple's Find My Friends feature that helps parents keep track of their children. It works through iCloud via an iPhone or iPad.
A recent survey by Ericsson found that 10% of people with wearables, including smartwatches, abandoned their devices, many within two weeks of purchase. One reason often cited was that wearables are too limited in their functionality, which includes too heavy an emphasis on fitness and health apps, instead of apps that could increase a person's safety and security -- like SOS.
When Ericsson suggested 20 different wearable applications to gauge interest in them, the survey group gave the highest ratings to apps for safety and security, like a smart locator or even a panic button capability.
Still, some observers questioned whether SOS would get people to buy an Apple Watch. The overall smartwatch category has been a disappointment to manufacturers so far, and SOS will not necessarily reach the level of a "must-have" technology.
"While the SOS function is an important capability, I wonder how many people will really buy a [smartwatch] because it can dial 911?" said Jack Gold, an analyst at J. Gold Associates. "Yes, I'll use it if I need it, but it's not my primary consideration" in buying a smartwatch.
Gold said it will take more critical functions and lower-cost smartwatches to get people to buy them in large numbers. "It will take a slow build-up of watch capabilities and new approaches over the next two to three years before we see mass adoption," he added.
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