▁One ▁( M 8 ), ▁the ▁successor ▁to ▁the ▁ 2 0 1 3 ▁HT C ▁One ▁( M 7 ). ▁There ▁are ▁two ▁versions ▁of ▁this ▁device : ▁one ▁running ▁Android ▁ 4 . 4 . 2 ▁Kit K at ▁and ▁another ▁running ▁Windows ▁Phone ▁ 8 . 1 . ▁ ▁HT C ▁One ▁M ini ▁ 2 , ▁the ▁HT C ▁One ▁M ini ' s ▁successor ▁ ▁HT C ▁One ▁( E 8 ), ▁a ▁lower - cost ▁variant ▁of ▁the ▁One ▁( M 8 ) ▁with ▁similar ▁spec s ▁but ▁a ▁poly car bon ate ▁body ▁and ▁a ▁single ▁ 1 3 - m eg ap ixel ▁camera ▁▁ ▁HT C ▁But ter fly ▁ 2 , ▁is ▁a ▁variant ▁of ▁the ▁One ▁( M 8 ) ▁with ▁similar ▁spec s ▁enc ased ▁in ▁a ▁poly car bon ate ▁body . ▁It ▁is ▁water ▁resist ant , ▁and ▁has ▁a ▁dual ▁rear ▁camera ▁( 1 3 - m eg ap ixel ▁main ▁camera ▁and ▁ 2 - m eg ap ixel ▁secondary ▁camera ) ▁▁▁ 2 0 1 5 ▁line up ▁▁ ▁HT C ▁One ▁M 9 , ▁the ▁ 2 0 1 4 ▁HT C ▁One ▁( M 8 )' s ▁successor . ▁ ▁HT C ▁One ▁M 9 + , ▁an ▁ups c aled ▁version ▁of ▁the ▁HT C ▁One ▁M 9 ▁ ▁HT C ▁One ▁M 9 + ▁Supreme ▁Camera ▁Edition , ▁a ▁phone ▁similar ▁to ▁the ▁HT C ▁One ▁M 9 + ▁but ▁with ▁a