How to get rid of third-party ads?

You can remove third-party ads as well as unlock unlimited Own Puzzles (located in the Create Puzzles section) by purchasing the Premium version of the app.

This is a one-time purchase that opens these functions for you forever.

To buy the Premium version open the Settings of the game (located at the top corner of the start screen) and find it at the end of the list.  The price will be reflected in your local currency. Also you should be logged into the Google account you are planning to use to play the game). 

Please pay attention that the Premium version does not affect the rewarded ads (appear when you want to get extra event points or coins).