With　the　rapid　advance　of　mobile　computing　technology　and　wireless　networking,　there　is　a　significant　increase　of　mobile　subscriptions.　This　drives　a　strong　demand　for　mobile　cloud　applications　and　services　for　mobile　device　users.　This　brings　out　a　great　business　and　research　opportunity　in　mobile　cloud　computing　(MCC).　This　paper　first　discusses　the　market　trend　and　related　business　driving　forces　and　opportunities.　Then　it　presents　an　overview　of　MCC　in　terms　of　its　concepts,　distinct　features,　research　scope　and　motivations,　as　well　as　advantages　and　benefits.　Moreover,　it　discusses　its　opportunities,　issues　and　challenges.　Furthermore,　the　paper　highlights　a　research　roadmap　for　MCC.