Apple uses LPDDR, which is what's used in all smartphones and most really thin laptops. LPDDR has the exact opposite design goal from HBM: LPDDR is optimized fo

Apple uses LPDDR, which is what's used in all smartphones and most really thin laptops. LPDDR has the exact opposite design goal from HBM: LPDDR is optimized for high bandwidth per pin to enable low pin counts, while HBM relies on advanced silicon interposer packaging to enable extremely high pin counts allowing for modest bandwidth per pin. The only similarity is that Apple puts the LPDDR in the package with the CPU, but it's an entirely different and more mundane packaging technology compared to what is used for HBM.