Programs stops work when I open them

Hello. On my two week old tablet some programs stops to work once I open them.

When I go into settings I get this message: "Samsung Galaxy has stopped working." I cant go to my settings.

This problems happen a lot, also with the Popcorn Time program (streaming videos). I get the same message "Popcorn Time has stopped working."

When these problems happends I just wait a second or two and then I have to close the program.

(NB! The programs who does not work are downloaded for android).

Is there anybody who know how to fix it? Thank you in advance!