Compare the lives of when they live under Jones and Napoleon. In what ways has Napoleon himself proven himself a similar tyrant?

The way that the animals live under Napoleon is essentially no different than the way they lived under Jones.  There is only one real difference that I see -- no animals are killed for food under Napoleon (although Boxer is killed for money, but at least it is after he is already pretty close to death).

Under Napoleon, the animals have little choice in what happens to them.  They have to do what Napoleon says or they will die.  The same was true under Jones.  To me, this means that little has changed.

Napoleon is similar to Jones because he is using the animals' work to make a comfortable life for himself.  He cares mainly about himself (and the pigs) and does not care if he is being fair to the other animals.