Tim Cook will almost definitely stick around until 2025 when he’s due for a 1 million share payout, and possibly a bit longer, if he’s not yet satisfied with the rollout of a major new product category (AR/VR glasses), but given that he’ll be in his mid-60’s by then, most speculate that he’ll turn over the helm to a new CEO. Columnist Mark Gurman considers the most likely candidates from Apple’s executive ranks.