The HTC One (M8) is powered by a quad-core Qualcomm Snapdragon 801 SoC, while the Samsung Galaxy S5 in India is powered by an octa-core Samsung Exynos 5420.
The HTC One (M8) has a volume rocker and SIM card tray on its right edge, but no power button. The Samsung Galaxy S5's power button is on the right edge.
The HTC One (M8) has its Micro-USB and headset ports on the bottom, while the Samsung Galaxy S5 has only a Micro-USB 3.0 port protected by a waterproof flap.
The HTC One (M8) has a innovative dual-camera feature for depth sensing and other effects. The Samsung Galaxy S5 has a heart rate monitor right next to its camera flash.