Usually there are buttons on the screen that you can just tap for that.
In email application for example, when you open an email, you automatically get a button to: Reply, Reply All, Forward, Delete and show keyboard. Also if you swipe the screen to the right, it will open the next email, if you swipe to the left, it will open previous screen.
If you just go to email app without clicking on an email, there are buttons to compose and search.
I'm sure there are others like this, but I mostly use email on mine and I know those very well.