I found the top mounted power button on the HTC One, which also acts as an Infrared port, is almost impossible to press when using the phone single handedly. In my experience the optimal position for the power button on a large smartphone is on the right side, as this allows one-handed access. The HTC One's power button is awkward to press without avoiding an uncomfortable grip.
HTC's capacitive button layout also left me disappointed. The new layout sees a back key on the left and a home key on the right. The latter felt particularly uncomfortable and almost completely unnatural. There's no multitasking button on the HTC one, so this menu is accessible by double tapping on the home button. A long press on the home button launches Google Now.
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