Your problem is not 'clarity' but focus. In the first photo where the cat is blurry, you can see that the background is sharp. This is a mis-focused shot. When you say you have to hold your finger on the screen...I assume you mean you press on cat's face so it focuses there.
This is what you should do: point the camera at the subject and once you are steady, a white box will flash over the main focus point and when the camera has achieved focus and is ready for you to shoot, the white box turns green, you press the shutter button and continue to hold the phone steady until the photo appears on the screen. If you move too early, the photo will be blurry due to camera shake.
HOWEVER, I have noticed on numerous occasions that the box turns green and the subject that the box is placed over is not in focus. This is because the focus engine for this camera stinks (as many of Samsung's features are). In that case, press the square, let it re-focus and check that the image is actually in focus. Samsung mostly has problems with mis-focusing close subjects in less than ideal light.
If the box is not focusing on the subject you want, press on the subject and the box will move to that subject and turn green. Check that the focus is correct and then take the photo. If it's not correct, press again.
You don't need to hold your finger on the screen. Once the box turns green, take the photo (while holding camera steady until final photo appears). If the box is red, try again until it turns green. Red usually means not enough light to focus or too close to focus.
Also, in low light situations switch to 'Night' mode.
Hope this helps.