Eye seeing Dog.

Jogging Buddy.

Guide dogs are assistance dogs trained to lead blind and visually impaired people around obstacles.
Although the dogs can be trained to navigate various obstacles, they are partially (red–green) color blind and are not capable of interpreting street signs. The human half of the guide dog team does the directing, based upon skills acquired through previous mobility training. The handler might be likened to an aircraft's navigator, who must know how to get from one place to another, and the dog is the pilot, who gets them there safely.
In several countries, guide dogs, along with most service and hearing dogs, are exempt from regulations against the presence of animals in places such as restaurants and public transportation.

What happened when the reverse occur? The dog gets old and is blind? a dilemma.

Just a thought.