Some devices don't create my Folder (android)

ionic-v1
#1

On my app, I render a div content into an image using the dom-to-image plugin.

I coudn’t think of another way to pick the rendered image and save on the device, so here’s my code.
80% of the devices create the storage folder and the code run just fine, but I don’t know why the others don’t.

$scope.baseString = '';

renderContainer = function(){
    var $node = document.getElementById('container');

    domtoimage.toPng($node)
    .then(function (dataUrl) {
        $scope.baseString = dataUrl;
        createFolderIntoDevice();
    });
};//renderContainer

createFolderIntoDevice = function(){
   window.resolveLocalFileSystemURL(
        cordova.file.externalRootDirectory, 
        onRequestFileSystemSuccess, 
        null); 
};//createFolderIntoDevice

onRequestFileSystemSuccess = function (fileSystem) { 
    var entry = fileSystem; 
    entry.getDirectory("TestFolder", {
        create: true, 
        exclusive: false
    }, onGetDirectorySuccess, onGetDirectoryFail ); 
};//onRequestFileSystemSuccess

onGetDirectorySuccess = function (dir) { 
    saveCardIntoDevice($scope.baseString);
};//onGetDirectorySuccess

onGetDirectoryFail = function(error) { 
    alert("Error creating directory "+error.code); 
};//onGetDirectoryFail

saveContainerIntoDevice = function(baseString){
    var myBaseString = baseString,
        block = myBaseString.split(";"),
        dataType = block[0].split(":")[1],
        realData = block[1].split(",")[1],
        folderpath = "file:///storage/emulated/0/TestFolder/",
        filename = 'Container' + Math.floor(Math.random() * (1000 - 143)) + 143 + '.png';

    savebase64AsImageFile(folderpath,filename,realData,dataType);

};//saveContainerIntoDevice

savebase64AsImageFile = function(folderpath,filename,content,contentType){
    // Convert the base64 string in a Blob
    var DataBlob = b64toBlob(content,contentType);

    window.resolveLocalFileSystemURL(folderpath, function(dir) {
        dir.getFile(filename, {create:true}, function(file) {
            file.createWriter(function(fileWriter) {

                fileWriter.write(DataBlob);
                
            }, function(){
                //error
            });
        });
    });
};//savebase64AsImageFile

b64toBlob = function (b64Data, contentType, sliceSize) {
    contentType = contentType || '';
    sliceSize = sliceSize || 512;

    var byteCharacters = atob(b64Data);
    var byteArrays = [];

    for (var offset = 0; offset < byteCharacters.length; offset += sliceSize) {
        var slice = byteCharacters.slice(offset, offset + sliceSize);

        var byteNumbers = new Array(slice.length);
        for (var i = 0; i < slice.length; i++) {
            byteNumbers[i] = slice.charCodeAt(i);
        }

        var byteArray = new Uint8Array(byteNumbers);

        byteArrays.push(byteArray);
    }

    var blob = new Blob(byteArrays, {type: contentType});
    return blob;
};//b64toBlob

I compiled this to Android 4.4