▁of ▁Win Obj C , ▁the ▁iOS ▁bridge ▁for ▁Universal ▁Windows ▁Platform , ▁in ▁ 2 0 1 5 . ▁Com b ined ▁with ▁its ▁own ▁implementation ▁of ▁C ocoa ▁Touch ▁and ▁underlying ▁APIs , ▁the ▁project ▁allows ▁the ▁reuse ▁of ▁iOS ▁Application ▁code ▁inside ▁of ▁U WP ▁apps . ▁ ▁On ▁Windows , ▁Object ive - C ▁Development ▁tools ▁are ▁provided ▁for ▁download ▁on ▁G N US te p ' s ▁website . ▁ ▁The ▁G N US te p ▁Development ▁System ▁consists ▁of ▁the ▁following ▁packages : ▁GNU step ▁MS YS ▁System , ▁GNU step ▁Core , ▁GNU step ▁De vel , ▁GNU step ▁C airo , ▁Project Center ▁IDE ▁( Like ▁Xcode , ▁but ▁not ▁as ▁complex ), ▁G orm ▁( Interface ▁Bu ilder ▁Like ▁Xcode ▁N IB ▁builder ). ▁These ▁binary ▁install ers ▁have ▁not ▁been ▁updated ▁since ▁ 2 0 1 6 , ▁so ▁it ▁could ▁be ▁a ▁better ▁idea ▁to ▁just ▁install ▁by ▁building ▁under ▁C yg win ▁or ▁MS YS 2 ▁instead . ▁ ▁Library ▁use ▁Object ive - C ▁today ▁is ▁often ▁used ▁in ▁tan dem ▁with ▁a ▁fixed ▁library ▁of ▁standard ▁objects ▁( o ften ▁known ▁as ▁a ▁" kit " ▁or ▁" framework "), ▁such ▁as ▁C ocoa , ▁GNU step ▁or ▁Ob j F W . ▁These ▁libraries ▁often ▁come ▁with ▁the ▁operating ▁system : ▁the ▁GNU step ▁libraries ▁often ▁come ▁with ▁Linux - based ▁distributions ▁and ▁C ocoa ▁comes ▁with ▁mac OS . ▁The ▁programmer ▁is ▁not ▁forced ▁to ▁inherit ▁functionality