save and compare screenshots for mobiles using appium not supported

[ghost]

Trying to make a visual comparison of the whole screen for an iphone 4s using appium and webdriverio/webdrivercss

My code:

var webdriverio = require('webdriverio'),
    webdrivercss = require('webdrivercss');

var client = webdriverio.remote({
    port: 4723,
    desiredCapabilities: {
        'browserName': '',
        'appiumVersion': '1.4.13',
        'deviceName': 'iPhone 4s',
        'device-orientation': 'portrait',
        'platformVersion': '9.2',
        'platformName': 'iOS',
        'app': '/absolute path to app/myApp.app'
    }
});

webdrivercss.init(client, {
    screenshotRoot: '../screenshots/moi',
    failedComparisonsRoot: '../screenshots/moi/diff',
    updateBaseline: true
});

client
    .init()
    .webdrivercss('moi', {
        name: 'moi',
        x: 0,
        y: 0,
        width: 320,
        height: 480
    }
    , function (err, res) {
        if(err)
        console.log("err..." + err);
        if(res)
        console.log("res..." + res);
    })
    .end();

console output:

RuntimeError: RuntimeError
     (JavaScriptError:17) An error occurred while executing user supplied JavaScript.
     Problem: An error occurred while executing user supplied JavaScript.

     Callstack:
     -> execute([Function])
     -> saveDocumentScreenshot("../screenshots/moi/moi.png")
     -> webdrivercss("moi",{"name":"btn","x":0,"y":0,"width":320,"height":480})

@christian-bromann maybe any idea?

[ghost]

@christian-bromann any update regarding this new feature "Webdrivercss for native app testing"

[christian-bromann]

@cwandja yes we set the corner stone with recent updates in WebdriverIO. We will updating this project soon.

[ghost]

@christian-bromann can you please leave a comment here when it is done? cheers!