To Queue a Job go into your Web Portal > Jobs > + New Job > and in the Assign To field select Queue tand the user group(s) that are able to accept the job.
You can also set an already created Job to Queue, by going to Jobs > View Jobs > select the Edit arrow for the Job and in Assign to select Queue and the user group(s) that are able to accept it.
On the App the job can be Accepted, Rejected and Rescheduled by swiping to the right on the job screen. The process of completing a job is the same as a job normally assigned to the user directly.