You can use the tns platform [add|remove|clean|upgrade] <platform> command to install, remove, or update the platform modules just like plugins. These are the tns-android and tns-ios modules you see listed in the prior tns info command. The application actually needs these platform-specific modules to be installed. By default, when you perform a tns run, it will automatically install them if they are missing. Occasionally, if the application refuses to build, you can use tns platform clean <platform>, and it will automatically uninstall and then re-install the platform which will reset the build process.