Coolsailing, I'm by no means a minimalist sailor, but it would be a lot less expensive to teach yourself how to read the wind without instruments. It's a good thing to know in case your electronics fail but not something one usually thinks about doing when all the conveniences are in front of you. We lost our windvane to a bird a few years ago and I don't miss it at all. I have wind apps but they don't tell me what's happening immediately around my boat. I record Beaufort scale readings in our log and rely on how the wind feels.
That said, I've used a netbook for navigation until this season when I'm going to experiment with the
Garmin app on my iPad. I found a waterproof case to mitigate some of that risk.