browser --> execute java script
"navigator.screenshot.save(function(error,res){
if(error){
console.error(error);
}else{
console.log('ok',res.filePath);
}
},'jpg',100,'myScreenShot');"
and cordova plugin add h t t p s://github.com/gitawego/cordova-screenshot.git
in iOS, only jpg format is supported in Android, the default WebView and Crosswalk are both supported