According to the official website of the developer, Line application can be used on Nokia Asha mobile devices or Nokia devices that uses Windows Phone. There isn't anything mentioned about the compatibility with Symbian OS. However, to check if your device can or can't run Line, visit the official Ovi Store, choose your phone model from the upper bar, and search for Line application. If there is a compatible version of the application with your device, it should appear among the results.