Optus has announced the availability of embedded SIM (eSIM) card technology on its mobile network, with the telecommunications provider unveiling its "Optus Number Share" product.
The "SIM-less" technology involves a permanently fitted SIM, around 10 times smaller than a nano SIM, being pre-installed in wearables to connect them without needing to pair with a smartphone via Bluetooth.
Optus Number Share will be available from September 22.
Optus said it will offer integration with Apple's Watch Series 3, which was unveiled earlier this week and includes cellular connectivity via eSIM technology, rather than relying on Wi-Fi or Bluetooth connections.
Optus' parent company Singtel enabled the eSIM across its own Singaporean 4G network in January, at the time saying it would charge post-paid mobile customers an additional monthly fee of SG$5.35 during the promotional launch period, after which it would cost SG$10.70 per month on a 24-month contract.
The announcement also follows Telstra on Wednesday adding phone call, data, and text messaging capabilities to wearable devices with the launch of its "Telstra One Number" eSIM product.
As the Telstra One Number product name suggests, it allows customers to use the same phone number across their wearables as they use on their smartphones, sharing data, call, and text inclusions from their mobile plan.
"Telstra One Number paves the way for a new generation of wearables with evolved designs and voice and data integration," Telstra Product Innovation ED John Chambers said.
"Up until now, customers have had to pair their smartphone with their wearable devices using Bluetooth to access calls, messages, and notifications on their wearables."
Chambers added that using eSIMs would also enable smaller wearable devices to be developed, such as health monitors and connected clothing.
Telstra One Number will initially be made available to post-paid consumers, and will in future be offered to prepaid consumer, enterprise, and small business customers with compatible wearable devices.
Samsung's Gear S2 Classic 3G was the first device to launch a GSMA-compliant eSIM last year, after GSMA released the eSIM specification in February 2016.
The eSIM specification has been backed by Apple, Samsung, Microsoft, Huawei, Sony, and LG, along with chip makers, SIM makers, and telecommunications carriers.
"The initiative does not aim to replace all SIM cards in the field, but is instead designed to help users connect multiple devices through the same subscription and will help mobile device manufacturers develop a new range of smaller, lighter mobile-connected devices that are better suited for wearable technology applications," GSMA said at the time.
It therefore has many potential use cases for machine-to-machine and Internet of Things (IoT) devices, GSMA said.