Race to Twenty Card Game app for iPhone and iPad

About
This card game designed to help understand how to always be the first person to reach 20.
Game play can be made more challenging by varying
target end number from default 20 to 40 for example.
start number from default of 0 to 10 for example
number of cards available to players, default is 11
odd numbers card only for player 1 or 2
even numbers cards only for player 1 or 2

more resources can be found here
http://iwant2study.org/ospsg/index.php/interactive-resources/mathematics

Interesting Fact
This app is created to support playing of adding up in creative and challenging ways.

Acknowledgement
This physical card game was originally shown to me and conceptualized by Theresa Heng.

My sincere gratitude for the tireless contributions of Francisco Esquembre, Fu-Kwun Hwang, Wolfgang Christian, Félix Jesús Garcia Clemente, Anne Cox, Andrew Duffy, Todd Timberlake and many more in the Open Source Physics community.

Network Learn together?
FaceBook Fan Page: https://www.facebook.com/Open-Source-Physics-Easy-Java-Simulation-Tracker-132622246810575
Twitter: https://twitter.com/lookang">https://twitter.com/lookang
YouTube: https://www.youtube.com/user/lookang/videos
Blog: http://weelookang.blogspot.sg
Digital Library: http://iwant2study.org/ospsg/