Los Angeles-based venture firm GRP Partners announced Wednesday that it has hired a new, entrepreneur-in-residence for the company, Sam Rosen, who was formerly the founder of SpeakerGram in New York City, was involved in 500Startups in San Francisco, and also has been involved with ScoreBig. According to a blog post by GRP's Mark Suster, Rosen will be relocating to Los Angeles to be involved with helping GRP to review deals, network with entrepreneurs, and work on his next company.