The trick is to make sure you get the latest Android Wear. That'll require an Android device. Not all iPhone owners will also own an Android device.
Edit: You'll need someone's phone for a few hours - the updates don't come all at once. But it's a matter of installing the Wear app on an Android device, pairing, installing updates. Then wipe the watch and pair with iPhone
It's not bad; I inadvertently did this trying to use the hacks to get my Moto 360 to work on my iPhone several months ago (which kinda worked but was really shitty). I just installed Android Wear on my old Android phone, paid it, it offered the update pretty quickly (though I can't remember if there is a way to force this or if it's only automatic), installed it and then I reset it.
