Similarities with 'As Good As It Gets'? SPOILERS AHEAD
Just for fun! I found some similarities. Too glaring, right?
A bitter old man who lives alone and practically hates everything around him. But once we know his back-story we start empathizing with him and his quirks start amusing us, some of which are: He hates someone's dog pissing near his house so much so that he threatens to kill the dog. He always takes the same seat in his favorite cafe.
He begins to change when he comes in contact with a woman younger to him. The woman has some medical issue with her child (taking care of her ill son in 'As Good...', pregnant in 'Ove')
Later he takes in a pet as there is no one to take care of it. He also allows a homosexual male, whom he ridiculed earlier, and who is abandoned by his father, to live with him.
Not claiming that the film is copied or anything. Just some harmless observations. 'Ove' is a beautiful film.