Devonport can be very attractive when there are activities going on such as art exhibits and festivals, otherwise it may be disappointing if you are the traveler looking for action. There's a lot to see and photograph, i.e. museums, old navy houses, Mount Victoria and Mt. North Head (which provide beautiful views of the city) the naval base, caves and the famous WWII tunnels, tangled corridors running from inside the two mounts. The food is above avarage, the best fish and ships in town is certainly sold there! (I would recommend the cafe by Victoria Theater, its the best in the area), friendly people and great for tennis/golf/water sports. Green-as, I would recommend for people who enjoy nature and long walks. Dont forget to go the beach side, it's big on the weekends, sunbath facing the city from the other side!
But in general, i would recommend Devonport as a destination to older people, not youngsters/party people AT ALL!!!!