Apples can be harvested from mid-summer to late fall depending on the variety and growing zone. To harvest fruit, avoid removing the stem by cupping the apple in your hand and tilting it upward while twisting to separate the spur from the branch...
Cherry trees grow well in most zones. Although if you want to get more technical, tart cherries thrive best in zones 4-9, and sweet cherries grow best in zones 5-9. Bush cherries (somewhat sweet) are hardy enough for zone 3. Thanks to modern plant breeding, there are now self-pollinating cultivars and dwarf root-stocks of both tart and sweet cherry trees.