Google some tops on the Internet. You can also read reviews on different companies. This usually helps to find good developers.

Now there are a lot of developing companies and outsourced developers. Moreover, now you can even find the top countries in which it is best to look for outsourcing specialists. I advise you to click here to see the best countries for choosing an outsourcing company, as well as the various parameters that you should pay attention to. Hope you find what you need.