The Smarty Ring is not an iWatch but pretty close in functionality. Bluetooth-enabled wearable gadget that allows users to check smartphone alerts and manage incoming calls right from their finger. One ring to rule them all and very much compatible with Apple products.
Not checked google trends on whether this is hot for wedding rings. To precisely see how they are getting around the otherwise big hurdle of sizing check this nifty link:
Retail price is 275$ If you order now you can save a whopping 100$. Available April 2014