I have visited Exeter a few times as I have friends that live in the town.
There are a few shops but the town itself is quite small and there isnnt really a lot to do shopping wise. There are some small independently owned shops (butchers etc) which I think it is always nice to see as opposed to just large chain shops.

There are a few nice pubs and a couple of nice places to eat and there is also a train station on the outskirts of the town.
There is also a bus service running from Crediton to nearby villages and also to Exeter City centre however the buses can be quite irregular and unreliable in my experience.
There is a beautiful church, which is worth looking at, and there is also a Farmers Market held on the first Saturday of the month which I enjoyed looking around.

There is a leisure centre but the majority of Exeter Cathedral is housing estates.
The people in Crediton always seem friendly and there is a good sense of community spirit.

I wouldnnt say this was somewhere you could come for a day out but it is fine if you just wanted to pass in and have a look around. I write this on helphound aswell.