How can you tell if apples are ready to harvest?

Are your apple trees heavy with fruit? Are you not sure if they are ready to pick yet? Here is a sure fire test:

1. They pull off the tree with relative ease.
2. Cut a sample piece open. If the seeds are brown, then you are good to go. If the seeds are still white then wait a little longer.
3. Taste it. It should be firm and sweet, but not powdering or tart (unless its a green variety)