What are the conditions under which you're getting blurry photos? OIS doesn't guarantee a movement-free shot (it helps, but it won't completely get rid of hand shaking if it's too bad), especially if your subject is moving in a low-lit situation.
If you're shooting in Auto Mode, your camera will focus more on letting more light in than keeping things in motion blur-free (it helps that the pixels are larger because the shutter doesn't have to stay open that long to get more light). If your particular scene is not-so-well-lit and your subjects are moving, you can try either Pro Mode and play with the Exposure settings or try the Sports mode.
If you're still having issues with that, I'd probably have the phone checked out. I haven't had any issues in normal scenes even with moving subjects. Sure, my dog's face will be blurry in a night shot of him chasing after a ball, but it'll be perfectly clear in a daylight shot at the park.