These methods should work fine for both Android and iOS. There some issues on the server-side (for example - problems with touch actions in WebView). These problems are going to be fixed in next releases.
Actually AppumDriver is abstract now and it is extended by AndroidDriver and IOSDriver because there are a lot of specific methods for each target platform. Some methods are implemented differently for Android and iOS. I think if there will be the supporting of WinMobile/FirefoxOS the number of methods like these will increase. So these classes were designed to avoid the possible problem of God Object.