There are all sorts of devices out there that will give you hr. However don't think that because a cyclometer has GPS that they are insulting your intelligence. I use a cyclometer with a gps because I like to look at my ride afterwards and compare my stats on certain segments of that ride. The times I ever followed a course on it in the ten years I've had it I probably could count on one hand. Like you, I know where I'm going.

Phones work too to record HR and other stuff, but I'd rather make sure mine is safely tucked away and not doing stuff that might drain it's battery fast. There are a few around here that have had their phones fall out of their mount and clatter to the pavement. I want my phone to be usable if I need it for the original purpose..... making a phone call.