此版本中的新功能：Ver 2.0 - Important bugs fixed and code optimization.
Ver 2.1 - New optimization code, auto resize for all phone resolution screen, new setting for a preferred speed.
Ver 2.3 - changed the mobile ads, this app is less size and needs fewer permits and be faster at the start.
Ver 2.4 - SDK update, new rate button in settings page.
Ver 2.5 : Update all SDK into this app in order to adhere new google ad policy.
Ver 2.6 : Update in order to activate a sdk features.