“Because WatchKit 1.0 is so limited and performance is so inconsistent, it’s hard to make Watch apps that are truly useful compared to just taking out your iPhone and using the full app. I believe this will always be the case to some degree, even after we get a native SDK.”
Great post from Marco on Overcast for Apple Watch.
Personally I’m going to wait until the full SDK is out. I don’t think my current apps would be a great fit for an Apple Watch companion app.