We　consider　Schrodinger　equation　in　R2+1　with　nonlinear　scalar　potential.　The　potentials　are　time-independent　or　determined　as　solutions　to　inhomogeneous　wave　equations.　By　constructing　a　modified　propagator,　we　derive　Kato-type　smoothing　estimates　for　the　nonlinear　Schrodinger　(NLS)　equation.　With　the　help　of　these　results,　we　prove　the　unique　solvability　of　the　nonlinear　Klein-Gordon-Schrodinger　(NKGS)　system　for　all　time　in　the　energy　space.　(C)　2014　Elsevier　Inc.　All　rights　reserved.