Google maps javascript not working properly

Hi, I have a question about google maps with javascript source. its working properly on browser and android 4.0 or below and also working properly on iOS 8.
and if I try on android kitkat or above maps not loaded.

Have you tried to debug your code?

I not yet try debug it. but, somtimes show alert 'the connection to the server was unsuccesful(file:///android_asset/www/index.html)