android 内购

1 找到public key的位置
https://support.google.com/googleplay/android-developer/answer/186113?hl=zh-Hans
https://support.google.com/googleplay/android-developer/answer/186113?hl=en

2 public key的安全设计
可以用xor字符串加密算法
https://developer.android.com/google/play/billing/billing_best_practices.html?hl=zh-cn
https://developer.android.com/google/play/billing/billing_best_practices.html

3 参考
http://leenjewel.github.io/blog/2014/11/21/google-play-in-app-billing-cai-guo-de-na-xie-keng/