Okay, there's the Apple Watch with official support from Dexcom, then there's Android Wear with community support for Dexcom, and finally, there's Dave Watch, the android App Widget based watch face for use primarily with Samsung Gear smartwatches, but can be used with any smartwatch that supports Wearable Widgets.
Anyway, I've added some cool stuff I thought I'd share. Here are a few pictures:
xdrip+ has some cool features to track and manage both insulin and carbs. Also, the app tries to forecast BG based on insulin and carb entries as well as BG "momentum" (how it's trending).
When xdrip projects you're going to go low, it tells you, and gives an estimate of how long until the hypo hits. I've added this to the display.
I also added display of current IOB.
Finally, when xdrip+ forecasts you are going to be above or below target based on accounting for insulin, carbs, and current BG, it will recommend a treatment (eat some carbs, take some insulin). I've added that information too, when it's present. While it's hard to see the 9.9U overlayed on the syringe, and the 50g overlayed on the hamburger, that's an artifact of taking the picture... it's quite clear and readable on the watch.
Oh, and before you ask, I simulated those recommended "treatments" by first telling xdrip I'd taken 10U in the upper picture, at which point it dutifully told me to eat 50g of carb based on my current BG (84), current momentum (heading very gradually down), and IOB.
I hit "undo" on that and then entered instead 50g of carb eaten. Not surprisingly it told me to take ~10U (9.9) of insulin.