The update is available now, and lets iPhone users not just see that a call is incoming (like most other Wear OS watches), but also to use the watches' onboard speaker to take the call if desired.
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This means Fossil's Gen 5 smartwatches are the first in the Wear OS clan to offer this kind of functionality with Apple's smartphones.
When Fossil unveiled its latest watches back in August, it indicated that an update along these lines was coming. It has now come good on that promise just a couple of months later.
According to 9to5Google, some users are reporting that the update actually also improves call quality for Android users too, indicating that Fossil has taken the opportunity to make some general quality of life improvements, too.
We were fairly keen on Fossil's fifth-generation watches at release - they've got nice designs, but the addition of that speaker was a mixed bag in terms of actual use. However, extending calling privileges to iPhone users does at least even the playing field a bit.
It will be interesting to observe whether other Wear OS watches can now match this support, or whether Fossil will be the only one to figure out how to match features across different phones. Although calling is a big feature, Wear OS is still lopsided on other counts.