FineUploader插件怎么限制手机端只打开相册啊

FineUploader插件怎么限制手机端只打开相册啊,
而且在手机端好像multiple: true的设置也没有效果，只能选择一张
$("#@(clientId)").fineUploader({
request: {
endpoint: '@(Url.Content("~/Picture/AsyncUpload"))'
},
template: "@(clientId)-qq-template",
multiple: true,
validation:
{
allowedExtensions: ['bmp', 'jpe', 'jfif', 'pjpeg', 'pjp', 'tiff', 'tif','jpeg', 'jpg', 'gif', 'png']
},
messages:
{
typeError: "请上传图片"
}
}).on("complete", function(event, id, name, responseJSON, xhr) {