I’ve done a little research on this subject and have become quite good at getting Nice, Great, Excellent and Curve Ball throws in Pokémon Go.
How To Throw A Curveball and Why You Shouldn’t
Firstly, how to get a curveball throw: Press and hold on the Pokeball, draw lots of circles as quickly as you can on the screen with your finger held down on the Pokeball. The Pokeball will start to spin in he direction of your circles. Throw the Pokeball as it’s spinning and you’ll get a Curveball with 10XP extra if it catches the Pokémon. Easy to do, hard to aim. Possibly increases the chances of catching the Pokémon against a non curveball throw hitting the Pokémon in the same place.
Here’s why I don’t throw curveballs anymore: It’s harder to aim and I’ve got quite good at throwing Nice, Great and Excellent shots with my special technique, which I’ll tell you next :p
How To Throw Nice, Great and Excellent Throws
A better way to increase your changes of catching a Pokémon and the XP for catching it, is to get a Nice, Great or Excellent throw…
To increase your chances of catching a Pokémon, Niantic say that you should imagine throwing the Pokémon through a hole (the ring that gets smaller). If you get the Pokeball stuck in the hole, you’ll catch the Pokémon. Therefore, the smaller the hole, the more chance an accurate throw will get the Pokeball stuck.
With this weird way of thinking about it in mind (really Niantic, this is a totally unintuitive system), when the ring is largest, it’s easier to get the Pokeball to land in the correct place to get the ball in the hole. But if the hole is large, you can only get a Nice throw. If the hole is smaller (therefore smaller to “hit”), you can get a Great throw. Great throws are quite easy to get once you know how. Excellent throws require an accurate throw with a very small hole.
Just to add to that confusion, Niantic have also stated that despite the above methodology, you shouldn’t aim for the hole, you should aim for the Pokémon. Therefore you just have to learn by trial and error, where to hit each type of Pokémon :s
Now, to make it easier to throw the ball exactly where you want it, I have a tip for you. Put your finger on the Pokeball and rest your other fingers on the side of the phone (off the screen). As you throw the Pokeball, run your other fingers along side of phone so it’s not possible for your throwing finger to do anything but travel in a straight line. Using this technique, you only have to worry about how fast and long to throw the ball to hit the Pokémon in the right place. You won’t have to worry about hitting the Pokémon off to the side or accidentally doing a Curveball.