For convenience and driver safety, I'd like to suggest that users be able to set up one (or maybe more) 'favorite' alerts. By far my most common alert is:

Hazard / Shoulder / Vehicle stopped

...and that takes 4 screen touches before it can be sent. Reducing the time that our eyes are off the road is good for everyone. If we could have a customizable pre-programmed alert such as this, I would love the app even more :).