Career Improvement Help

Hey guys I have 5.5 years yoe in IT overall, I have worked as Java Developer for 1.5 yrs and currently for past 3.5 yrs. I've been working as Apigee developer. I'm thinking of completing any certification or any course to move to different stream inside Development itself. Please suggest on any certification or course that might land me in better job as developer, also, it would be good, if I have more scope on development or code side.