How to safely shut down or force shut down HTC devices

HTC Desire 310 HTC Desire 310
HTC Desire 310 dual sim HTC Desire 310 dual sim
HTC One (M8) HTC One (M8)
HTC One (M8) CDMA HTC One (M8) CDMA
HTC Desire 210 dual sim HTC Desire 210 dual sim
HTC Desire 616 dual sim HTC Desire 616 dual sim
HTC One mini 2 HTC One mini 2
HTC One (E8) HTC One (E8)
HTC Desire 516 dual sim HTC Desire 516 dual sim
HTC One (M8) dual sim HTC One (M8) dual sim
HTC One Remix HTC One Remix
HTC Butterfly 2 HTC Butterfly 2
HTC Desire 510 HTC Desire 510
HTC One (E8) CDMA HTC One (E8) CDMA
HTC Desire 820 HTC Desire 820
HTC Desire 820 dual sim HTC Desire 820 dual sim
HTC Desire 820q dual sim HTC Desire 820q dual sim
HTC Desire 612 HTC Desire 612
HTC Desire Eye HTC Desire Eye
HTC One (M8 Eye) HTC One (M8 Eye)