This is my second apple trees to die in the last month, I think that it maybe fire blight but that is just a guess. Took a few pictures, any info or advice would be greatly appreciated.
There are no obvious signs of fireblight there. I lost a tree last week to fireblight and by the base it was blackened; I don't see any blackened wood in your pictures. So I would guess some other problem in the rootstock or graft union.