If such problems appear, it is recommended to restart the server (by escaping the server window and going to the 'New Exercise' menu and entering again). Then in the browser click the address field to make sure that the address there is the same as in the iPhone (e.g. "http://10.0.2.2:8080") and press ENTER in order to connect to the server again.

IT IS NOT RECOMMENDED to use the 'REFRESH' button, as it may cause some data to be sent again to the iPhone, which may result in downloading the same course again.

In case of further problems, you can restart both the application and the browser.