Nintendo Switch can’t save back-ups
 

All your saved games could be lost to history

The new Nintendo Switch will not allow you to backup the save files for Nintendo Switch games.

According to a company faq, Nintendo says that save data is kept on the system’s internal storage and “cannot be saved or copied to a microSD card.”

If the internal memory fills up, the FAQ says some of it will need to be deleted to make room for new save files.
http://fudzilla.com/news/games/43036...-save-back-ups