Is it on Dwarfing Root Stock or full growth roots? If dwarf. Cut back any of this seasons extensions to 3-4 leaf axils now (ASAP) and reshape, winter prune, in February before regrowth starts. If large go carefully on any ladders and cut it back to where you want it in the winter when no growth. So you can get the shape and size you want. It may take time to revamp itself and get going again. Try to open out the middle of the tree while you do this.