SMS under the magnifying glass, their function today

Given the increasing increasing competition through messaging services like whats app, Skype or Viber for smartphones it seems surprising, that the sending of SMS messages is still booming. According to current projections of the Federal Network Agency be directed 2011 round 55 Reach their recipient billion short messages via SMS. The reason is according to opinion of experts in the drafting of the respective. more…

JavaScript replace all css background images with retinal images

If you are faced with the problem, that dynamically generated CSS background images used, to images on a Web page to represent and this then also for retina display you want to look good, can I use the following script. It additionally checked via an AJAX request, If the images exist / exist.

A prerequisite is, that a naming convention for non-retina used images and retina is such as:

for non-retinal images


for retinal images

<!--Retina Fix for dynamic background images-->
        <script type="text/javascript">
            function isRetinaDisplay()
                var dpr = 1;
                if(window.devicePixelRatio !== undefined) dpr = window.devicePixelRatio;
                return dpr >= 2;

            var notRetinaString = "@1x";
            var retinaString = "@2x";

            $(document).ready(function() {
                //if we have a retina display
                    //select all elements having background images
                    var $elementsWithBackground = $('*').filter(function() {
                        if (this.currentStyle)
                            return this.currentStyle['backgroundImage'] !== 'none';
                        else if (window.getComputedStyle)
                            return document.defaultView.getComputedStyle(this,null)
                                .getPropertyValue('background-image') !== 'none';
                    //replace their background-image with retina images
                    $elementsWithBackground.each(function( index ) {
                        $backGroundImage = $(this).css('backgroundImage');
                        //when it is no retina image
                        if($backGroundImage.indexOf(notRetinaString) !== -1)
                            //replace with retina image
                            $newBackgroundRetinaImage = $backGroundImage.replace(notRetinaString,retinaString);
                            $newBackgroundRetinaImageUrl = $newBackgroundRetinaImage.replace('url("','').replace('")','');
                            //check if retina file exists
                            var $myThis = this;
                                cache: true,
                                success:function() {
                                    $($myThis).css('backgroundImage', $newBackgroundRetinaImage);
                                error:function() {
                                    console.log("no retina image found for: " + $backGroundImage);


JavaScript check function for retina display

To check, If a device with Retina-Display (new iPhone or Mac Book) surfing on the page, can I use the handy function:

            function isRetinaDisplay()
                var dpr = 1;
                if(window.devicePixelRatio !== undefined) dpr = window.devicePixelRatio;
                return dpr >= 2;

ActionBarSherlock design

ActionBarSherlock is a framework for Android to implement an ActionBar before Android version 3.0, where there is a native ActionBar.

Example of action bar with its own design under Android 2.3.3

In addition, you can use many functions,even the native ActionBar makes not possible, You can get the best an overview through the installation of the Sample App on an Android device.

One difficulty of the framework is in the individualization of design, This is possible without the very difficult Online style generator for ActionBarSherlock. With this amount of time can be save, absolutely to recommend!

Enabled search box in action bar


affordable hardware for iOS development: Mac Mini Tuning

If you want you plan to enter into the iOS development program and its own app, one needs necessarily a Mac, which is not exactly cheap. In the following article I will describe, as I for 350 € (November 2012) I bought a Mac to develop my iPhone apps and this upgraded for Xcode.

For iOS development for iPhone and iPad you need a Mac with an Intel processor mandatory. Unfortunately, these do not have particularly low :(

Furthermore, you need mandatory for programming Xcode IDE, to test for iPhone and iPad, and to bring the app to the Store.

The latest version of Xcode (4.5 current) turn necessarily requires Mac OS X 10.7, what the minimum requirements at least 2GB of RAM and an Intel Core 2 Duo needed (Nights, an Intel Core Duo is not enough!).

As an effective alternative, I bought a used Mac Mini with reason


Comparison of Augmented Reality Framework for Android

project nameMixingDroidARAndARvuforiawiktitudeandroid-augment-reality-framework
total ratingBCDA-BF
project urlMixingDroidARAndARvuforiawiktitudeandroid-augment-reality-framework
licenceGNU GPL v3GNU GPL v3GNU GPL v3Anonymous Data collection by Qualcomm,
Attribution License, the logo must be shown ether in loading, splash or credit screen license
not free, 599€ per App PricingApache License 2.0
version0.9.2??1.5.9.?initial version
latest build22.08.2012??22.02.2012?01.12.2011
tested Devices/Android Versionokno informationgoodvery good?
tested Devices URLLinkLinkAndroid 2.2 and newer, iOS 4 & 5.?
getting startedLinkLinkLinkLink?
Sample VideoLink
sample appLinkLinkLinkLink and Link
special featuresespecially for 3D Objects (with commercial licence)for ios and androidruns in webview (like phonegap), easy implementation for android, ios etc but performance issues may occur, very good customizable
conclusionactive community and steady buildsfew documentation and no information about tested devicesprojects is not maintained any morevery good documentation and device support, critical licence and complex intital setupnot free and few informations on the website, might have performance issues but easy to implement with HTML5project is not maintained any more


I chose Mixing decided, which gecodet well, but less well documented is. Is it very easy to own data or Wikipedia to put data on the camera and simultaneously view the same data as on Google Maps markers.

Vuforia to appear for the development of Android / iPhone solutions of suitable Kanditat be, However, when required under the license, that user data to the Qualcomm server are sent and the user must be informed:

Excerpt from the license of Vuforia

“You must inform end-users of your application that certain types of anonymous usage data is collected by the Vuforia SDK and sent back to Qualcomm servers.”

“(i) the collection by QUALCOMM and/or its affiliates of Statistics from the Software (including but not limited to: (a) information about the end users’ Such devices have device unique identifier, make, model, operating system name and version and kernel version, (b) information about our Software used to create your software or augmented reality end user application such as the SDK version and device profile, and (c) information about your software or augmented reality application and its use such as settings (e.g., camera resolution settings, configuration settings), start and stop dates and times, camera on/off events, target image obtained/lost events, and other general usage information (collectively “Statistics”)).”