But please remember to not use any detergents, window cleaner or any other chemicals. Use only water and a soft terry cloth towel. The oleophobic coating on your screen can be damaged by soaps. This means your screen will show fingerprints much sooner than it would by simply wearing out over time.
You can re-apply an oleophobic coating using 3rd party solutions such as that found on Amazon. But most/all 3rd party oleophobic coatings have mixed reviews.
So, no soap for your S5!