You can use the Home Button of the Samsung Galaxy S4 for answering incoming calls. This is much more comfortable, as to accept calls via the display, where you have to wipe the green phone circle with your finger.
However, you have to activate the function "Pressing the Home key" in the Android settings to use it.
We show you, where you can enable this option in the system settings of the Samsung Galaxy S4:
Therefore open the phone App from the Homescreen of the Galaxy S4. If it is open and you see the keypad, tap on the top right where the three vertically dots are arranged, to unfold a small menu. Select in this "Settings".
Go now to: Call -- > Answering and ending calls.
In this submenu, you now find a section "Answer Calls By". Select here "Pressing the Home Key" by posting a hook in the corresponding check-box . That's it. Now, if you receive a call on the Samsung Galaxy S4, you'll just have once again press the home button and the call is answered.