Understood, the Taptic Engine (haptic feedback) is a really great feature that Apple also took to their MacBook trackpad (actually, not sure which came first). They've removed one extra point of mechanical failure and gave their laptops and phones a consistent feel with minimal delay (instead of a vibrating motor). A disassembled Taptic Engine is actually a bunch of small coils of different sizes and oil filled inside. Quite the engineering masterpiece.