In-process trapping for service substitution in hosted applications executing on mobile devices with multi-operating system environment

The invention provides in some aspects a computing device that includes a central processing unit that executes a native operating system including one or more native runtime environments within which native software applications are executing, where each such native software application has instructions for execution under the native operating system. One or more hosted runtime environments execute within the one or more native runtime environments, each of which hosted runtime environments executes hosted software applications that have instructions for execution under a hosted operating system that differs from the native operating system. A first hosted software application executing as a first process of the hosted runtime environments includes an instruction that references a member (hereinafter, "referenced member") of an object defined by an object-oriented programming (OOP) class ("referenced class"). The process executes that instruction utilizing data and/or code (hereinafter, "substitute member") other than that specified by the referenced class as the referenced member. As used here, a "member" of an object is any of a method member and a data member.