The downloaded applications have an increase in cache as time goes by, therefore they can take up a lot of space on your internal memory.
One of the applications that can show you how much cache an application has made and gives you the power to manage them is ZDbox.
Download and Install the app from Google Play and then start it.
Now you can see specifically how much cache every application has stored.
This part of the software gives you the option of removing the cache stored from Google applications.