I would like to learn Korean on my different devices, Mac, iPad and MS Surface, but I have no clue, how the program remembers how far I had already advanced on one device, when I continue with another. There is apparently no way to log in with my ID and Password, so that the program knows who I am. This feature probably exist, but it is difficult to find out where and how.

Note from Rocket Languages: Hi Jac, thanks for your feedback. Someone of our customer support team has reached out to you to solve this issue. All the best with your Korean learning! Your Rocket Languages Team