Mobile Website Testing Frameworks

I have been looking into testing mobile websites using services such as Perfecto Mobile and BrowserStack. Are there any (significantly) cheaper alternatives? Currently, I am using Selenium and have a framework for desktop browsers built out. Perfecto Mobile (with a minor change) allows us to use the same Selenium code to run on mobile browsers. If there is a similar product out there or if anyone uses an amazing alternative please don't be shy!