Designers and developers will appreciate the newly released retina iPad GUI elements template available now as a free PSD download from Teehan+Lax. Based on iOS 5.1 and the new iPad’s retina UI elements, these PSD files are an excellent resource for quickly mocking up iPad apps, workflows, and general iOS concepts.

You’ll need Adobe Photoshop to properly use the PSD file and it’s intensive layering, but the excellent Photoshop CS6 beta is still free to download and use until the final release comes out later in the year.

• Download the PSD template free from Teehan+Lax

We’ve posted a lot of these UI element and iOS and OS X design templates here before because they’re so useful for both developers and designers. If you missed some of those past posts, varoius PSD templates are available for OS X Lion elements, non-retina iOS UI, iPhone & iOS 5 UI, and even retina iOS icon templates.

Ever wanted to view source of a webpage from an iPad or iPhone? Unfortunately, mobile Safari doesn’t include the feature on it’s own, but with the help of a custom bookmarklet you can view source of any web page right in iOS. This awesome tip comes from Michelsen.dk, and here’s how to set it up:

1. Bookmark this page (or any other) with Safari on an iPad, iPhone, or iPod touch and name it “View Source”
2. Click here to view the bookmarklet javascript and Select All -> Copy
3. Tap the Bookmark icon at the Safari new browser screen and tap on “Edit”, then tap the bookmark you saved in step 1
4. Paste the javascript code you copied in step 2 into the URL bar and save the changes by tapping “Done”

Now when you want to view a web pages source, open the Bookmarks menu and select “View Source”, the source code will appear in highlighted syntax with clickable source urls.

One thing to note is that the javascript being used here sends the page to the michelsen.dk server for processing, if you’re not comfortable with that there are other solutions out there but they won’t highlight the syntax and aren’t nearly as elegant overall.

A similar tip utilizes an edited bookmark to let you run Firebug with Mobile Safari on an iPhone or iPad too, which may be a bit more useful for developers.

Found via ShawnBlanc on Twitter, you can follow us there too

Web developers and website owners pay attention: you need to set a retina-ready iOS bookmark icon. Called an Apple Touch Icon, these custom images become the icon that is displayed on a users home screen when they bookmark a website on an iPad, iPhone, or iPod touch. Without a custom apple-touch-icon set, users will get a boring and often ugly thumbnail of the web page itself, and without using a retina-ready icon, the bookmarks icon will look pixelated and generally awful on the new iPad screen. Here’s what you need to do:

1) Create the Retina-Ready iOS Icon

Use a template or design your own. I used the easy DIY retina icon kit mentioned in a previous post, it’s a PSD file that makes designing nice looking iOS icons as easy as a click or two. Paste in a website or company logo and you’re pretty much good to go. If you don’t have something to edit PSD files, Photoshop CS6 beta is excellent and free to download and use until the final version comes out later in the year.

2) Save as PNG & Name the Retina Icon as Desired

The icon must be a PNG, and it must be named one of two things. Each file name offers a slightly different appearance of the icon as displayed on a users home screen:

• “apple-touch-icon.png” will add the highlight bubble overlay to the icon
• “apple-touch-icon-precomposed.png” will display the icon as originally created, without the highlight overlay

Use the latter -precomposed option if you created your own highlight, or if you want the icon to appear more flat without ubiquitous bubble that appears on most of Apple’s default icons.

3) Upload the Touch Icon to the Base Web Directory

Use an SFTP client (OS X includes FTP in the Finder, and CyberDuck or Filezilla are free) to copy the apple-touch-icon.png file to the root web directory. This is usually the same location that the sites main index file is located. Once uploaded, confirm it’s in the proper location by opening a web browser and going to “http://SITEURL.com/apple-touch-icon.png” and making sure it loads.

Here is an example of a 512×512 retina-ready bookmark icon from OSXDaily.com:

Notice that without the -precomposed flag, the above icon will display the highlight bubble. You can see the difference between the two by comparing the actual icon to the one shown in screenshots as the bookmark.

4) Use an iOS Device and Bookmark the Site

This is the easiest part, grab an iOS device (preferably an iPad 3 to confirm the retina aspect) and open Safari. Refresh the web site you uploaded the icon to, and then tap the arrow icon and select “Add to Homescreen” name the bookmark, then return to the Homescreen to confirm it’s there.

Despite being 512 x 512 pixels, the retina icon will scale down fine on older iPhones and non-retina devices. If you really want to, you can use CSS and HTML to display different sized icons to different devices, but it’s really not necessary.

Now if someone bookmarks your web site on an iPad with a retina display, it will look a lot better on their home screen. That’s really all there is to it. And yes, we’ve written about the Apple touch icon before, but it deserves another mention now that iPad 3 demands significantly higher resolution icons and graphics.

It’s rare that app developers and web developers double as graphic designers, leaving some apps and websites to include fairly hideous iOS icons. As we’ve said before, icons matter, however superficial they may be, so instead of shipping an app or site with an ugly icon do yourself a favor and download this do-it-yourself retina icon kit.

The DIY template from KillerIcons comes as a deeply layered and easily workable PSD file containing a 512×512 app icon, letting you easily create a very attractive icon just by switching on or off some layers, adding an element or two, and adjusting as necessary. PSD’s are best opened with Photoshop, but if you don’t have it go ahead and download CS6 beta for free and use it until the final version comes out, the template works fine.

• Get the free DIY icon kit from KillerIcons.com

These icon templates are useful website owners as well, use them to create an Apple touch icon PNG file to set as a custom bookmark icon for iOS home screens.

Shown below are the base template styles, but the possibilities are practically endless just by changing colors, borders, or hiding and showing certain layers.

You can see several sample retina icons I made quickly for OSXDaily below.

There are also some more basic retina icon templates available if you are looking to start from scratch or just want something less fancy.

iOS developers and hackers should get a kick out of this. By downloading a few mobileconfig files, you can enable hidden debug settings for Messages, Bluetooth, and FaceTime that log activity and events for each protocol. What you do with that information is entirely up to you, but there’s definitely some room for learning and exploration here.

To enable the debuggers, load this page on an iPhone, iPad, or iPod touch and click each link below, then click “Install” to download a profile to the corresponding debugger:

• iMessage Debugger
• FaceTime Debugger
• BlueTooth Debugger

These can easily be removed afterwards by going to Settings > General > Profiles

No jailbreak is required to use these, but thanks to the renowned jailbreaker Chronic for bringing the debuggers to the public.

If you’re spending the time and money to develop an iOS app, don’t skimp on the icon. This may sound like silly advice, but the fact is a good icon can make your app stand out in the App Store and on a users home screen, encouraging both downloads and use.

If you’re not a designer it can be challenging and expensive to get a good icon made, but thanks to Louie Mantia on Dribble, you should be able to create a tolerably decent one yourself using a retina iOS app icon template. The template come as a nicely layered PSD file and covers a variety of sizes for the icon, but perhaps most importantly with the new iPad out is the 512×512 pixel template. Start big and refine as you go down, you should have a gorgeous iOS icon in no time.

• Check out the app icon template on Dribble or download the PSD directly

This will be useful even for web designers and developers who want to use it as a template for the apple-touch-icon.png iOS bookmark icon that appears on a Home screen whenever an individual bookmarks a site.

Icon Sizes and Use
Here is a list of where you will encounter the following icon sizes:

512 – App Store
144 – Retina iPad Home Screen
72 – iPad Home Screen
114 – Retina iPhone Home Screen
57 – iPhone Home Screen
96 – Retina iPad Spotlight
48 – iPad Spotlight
58 – Retina Settings
29 – Settings

Speaking of helpful PSD files, don’t miss the iOS 5 GUi elements and OS X Lion GUI PSD, both are helpful for mocking up apps.

Hat tip to @AppleSpotlight on Twitter, you can follow us there too

Xcode is Apple’s developer suite for iOS and Mac OS X, it’s necessary if you intend to be write apps for either OS and installing it includes a number of other useful utilities other than the main IDE itself. The additional aspects include things like the Interface Builder, iPhone Simulator, Quartz Composer, Dashcode, gcc, dtrace, perl, python, ruby, and much more that has use beyond core iOS and OS X development, adding valuable utilities to tweakers and administrators toolkits.

Installing Xcode is just a matter of downloading it from the Mac App Store, but what if you want to remove Xcode? Doing so is not the same as uninstalling general Mac apps or even ditching the default apps because Xcode has a much larger footprint, so to uninstall Xcode you’ll need to venture into the command line.

Update: Our readers pointed out that Xcode 4.3 simplifies this process considerably by bundling Xcode into a single application. Therefore, this guide is most relevant to older versions. XCode 4.3 and later should be able to uninstall like any other Mac app. Thanks Mike & Peter!

Completely Uninstall Xcode

This will remove everything pertaining to Xcode from a Mac:

• Launch the Terminal, found in /Applications/Utilities/ and type the following:

sudo /Developer/Library/uninstall-devtools --mode=all

• Confirm the admin password (required for sudo) and let the scripts run

Don’t Forget to Delete the Install Xcode Application
If you uninstall Xcode, the original Install Xcode application is probably still sitting in your /Applications/ folder as downloaded from the Mac App Store, don’t forget to delete this too otherwise you are wasting 1.8GB of disk space.

Why Uninstall Xcode?

If you don’t use Xcode or it’s accompanying utilities it’s a good idea to uninstall the suite. Why? The simplest reason is because Xcode takes up a lot of disk space, generally a minimum of 7GB of disk space is consumed by the installation, and the installer application alone is another 1.8GB, that’s a lot of storage capacity taken up by something that is potentially getting no use.

Now that we’ve covered the basic process of uninstalling everything to do with Xcode and why some people would benefit from doing so, we’ll dive into some more specific information and some other uninstall options that could be useful to some users.

First, the the above uninstall command with -mode=all actually just runs three separate scripts making the uninstallation process easier, for those who are curious those separate scripts are:

/Library/Developer/Shared/uninstall-devtools
/Library/Developer/4.1/uninstall-devtools
/Developer/Library/uninstall-developer-folder

These do not need to be run independently, although you could chose to do so if you wanted to, more on that below.

If you want to selectively uninstall parts of Xcode rather than everything, use the commands below. These are not necessary if you run the above –mode=all command.

Uninstall Xcode’s Unix Development Toolkit

If you only want to remove the command line side of things, you can do that with this command:

sudo /Developer/Library/uninstall-devtools --mode=unixdev

This is actually linked to the aforementioned “/Library/Developer/Shared/uninstall-devtools” script. Personally, I think the unix toolkit is one of the most useful aspects of installing Xcode so I’m not sure why you’d want to do this, but it’s nice to know you can.

Uninstall the Xcode Developer Folder and Contents Only

This will keep other aspects of Xcode intact but will remove everything within the /Developer directory:

sudo /Developer/Library/uninstall-devtools --mode=xcodedir

This command is basically a shortcut to the previously mentioned “/Developer/Library/uninstall-developer-folder” script. If you want to ditch the /Developer directory, run this command rather than manually deleting it through the Finder.

Uninstall Xcode System Support

Selectively uninstall Xcode’s system support only (not recommended):

sudo /Developer/Library/uninstall-devtools --mode=systemsupport

This command just runs the following scripts: “/Library/Developer/Shared/uninstall-devtools” and “/Library/Developer/4.1/uninstall-devtools”

That just about wraps it up. You may be able to accomplish some of these tasks with an removal utility like AppCleaner as well, but for best results it’s a good idea to stick with the solution bundled with Xcode itself.

Apple has seeded iOS 5.1 beta 1 to developers, the build is 9B5117b and runs on iPhone 4S, iPhone 4, iPhone 3GS, iPad, iPad 2, and iPod touch 3rd and 4th gen. For those in the iOS developer program, you can download the iOS 5.1 beta right now directly from Apple’s dev center as IPSW files. Alongside the iOS 5.1 beta came a new build of Xcode 4.3, which is also required for developing anything for iOS 5.1.

The 5.1 beta notes include many mentions of bugs, you can read the full release notes on 9to5mac if you’re interested. They also uncovered references to an unreleased iPad 2 model in the beta, which they presume is for the Sprint network.

Stanford University’s School of Engineering has released full HD videos and slides of their Fall 2011 “Developing Apps for iOS” course. The lectures and lessons for CS193P are focused on iOS 5 and downloadable for free from iTunes University, offering a great look at beginning iOS development through the eyes of a world class engineering school.

• iTunes U & Stanford: iPad and iPhone Application Development (iTunes link)

If you haven’t downloaded any courses from iTunes before, a new section in the iTunes Library sidebar titled “iTunes U” will appear to contain the lessons.

Stanford’s description of the course is as follows:

Tools and APIs required to build applications for the iPhone platform using the iPhone SDK. User interface designs for mobile devices and unique user interactions using multitouch technologies. Object-oriented design using model-view-controller pattern, memory management, Objective-C programming language. iPhone APIs and tools including Xcode, Interface Builder and Instruments on Mac OS X. Other topics include: core animation, bonjour networking, mobile device power management and performance considerations.

Official prerequisites to the course are: C language and programming experience, and recommend experience with UNIX and object oriented programming. You’ll obviously need a Mac, Xcode, and the iOS SDK installed as well.

• Download Xcode 4.2 from iTunes – free
• Install the iOS SDK – free

Stanford University has made it a tradition to offer select courses for free online, including past iPhone development classes and the currently ongoing “Intro to Databases” course.

If you missed out on the $99 HP TouchPad deals that seem to have the entire tech web in a frenzy, don’t forget that you can experience WebOS for free right now on Mac OS X, just by using the SDK’s emulator. You’ll need to download VirtualBox and then the WebOS SDK which comes as a preconfigured virtual machine, but then you can toy around in WebOS and get a feel for the (possibly defunct) touch OS.

Here’s what you’ll need to get started:

• Download VirtualBox 4.0.12 for OS X (direct download link)
• Download Palm WebOS SDK (direct download link)

Installing the actual emulator is simple, even more so if you have any experience running virtual machines. Just download and run the WebOS SDK installer and when it’s finished the emulator will appear in /Applications ready for you to play around with.

It’s that simple, but if you need any more assistance you can read more on developer.palm.com.

Heads up to @mattgemmell on Twitter for the idea.

Whether you’re a UX or UI designer, app developer, or just want to create some mockups of Mac OS X Lion apps for fun, don’t miss these free OS X Lion UI Element kits from designers Jonatan Castro and Joshua Geiger. The GUI kits come as well labeled multi-layered PSD files that have all the main user interface elements from OS X Lion, ranging from sliders, dials, checkboxes, buttons, tabs, just about everything you can think of.

Download Lion UI Kit PSD file from Dribbble (shown above)

Download Lion UI Kit from SuiteTuts (shown below)

The two kits are slightly different and combine to be fairly complete, with the second kit focusing more on Desktop and Finder elements. The only thing I can find missing is the blue active button you see in things like Save dialogs, but chances are the PSD files will be updated to include that sometime in the near future, and regardless both are well worth the free download.

You can also download similar free GUI element PSD files for iPhone and iPad mockups too.

Want to learn a new programming language? Python is one of the hippest languages in use these days, but why pay for books and coursework when you can do this all on your own, for free, on your Mac? You can do exactly that with Dive Into Python 3, which has been made available as a free download online or as a PDF.

A couple notes, the book is for Python 3, but Mac OS X Lion bundles Python 2.7, so you’ll want to download the latest version. Here’s all you’ll need to get started:

• Xcode 4.1 – free download from the App Store
• Text Editor with Python syntax highlighting – Xcode works for this, or TextWrangler is highly recommended too, it’s the free little brother to BBEdit
• Python 3.2.1 for Mac OS X 10.6 and 10.7 (direct link, other OS versions here)
• Bookmark DiveIntoPython3.org or better yet…
• Download the entire book as a PDF and example files, for free – you can then save and open the PDF on your iPad for quick reference if you want

Thanks to Mike for the link to HackerNews, where the discussion thread also include recommendations for the official tutorial on Python.org and the accompanying reference guide as two additional great resources for learning.

Update: Another good Python book that is available for free online viewing is Learn Python the Hard Way, thanks to those who recommended this one.

A new addition to Mac OS X Lion and Xcode 4.1 is a utility called Network Link Conditioner, a highly customizable tool that lets you simulate a variety of common internet connectivity speeds. The utility is aimed at Mac and iOS developers so they can test their apps response times on a variety of network conditions, but it’s also extremely useful for IT admins, network administrators, and web developers.

• Download and install Xcode 4.1 (App Store link) – free download for OS X 10.7 users
• After Xcode is installed, head on over to:

/Applications/Utilities/Network Link Conditioner/

• Double-click on “Network Link Conditioner.prefPane” to load the utility into System Preferences

You can start using the bandwidth simulator right away. Network Link Conditioner is fairly self explanatory, just select a bandwidth profile that you want to simulate and click the “ON” button to activate it immediately. The default choices are:

• 3G – Average Case, Good Connectivity, or Lossy Network
• Cable Modem
• DSL
• Edge – Average Case, Good Connectivity, or Lossy Network
• Wifi – Average Case, Good Connectivity, or Lossy Network

If you find the existing bandwidth profiles too limiting, click on the little lock icon in the lower left corner, and then onto the “Manage Profiles” button in the bottom right to create or edit a new profile. Here you can set things like downlink and uplink bandwidth, up and down packets dropped, response delay, and even DNS delay.

If you do any sort of development work, network administration, or anything else that requires testing potential users internet connectivity speeds, be it an iPhone app, usage of remote networks, or a web site, Network Link Conditioner is highly recommended, install it now.

iCloud Beta is now live for developers to access, and we know what the pricing plans look like, but average users are left just looking at screenshots for now. Just kidding! If you want to check out iCloud’s very iOS-like Springboard and web apps, and you don’t have a developer account, you can use this cool little trick from @devongovett on Twitter:

Access iCloud Springboard without an Account Using Safari or Google Chrome

• Go to iCloud.com and ignore the login credential screen
• Right-click anywhere on the iCloud.com page and select “Inspect Element”
• Click on the ‘Console’ button on the far right of the element inspector
• Paste the following into the Javascript console:

CloudOS.statechart.gotoState("active.springboard")

• Hit the Return key and skirt right past the login screen and into the iCloud springboard

I have confirmed this works in Safari and Chrome and presumably it works the same in Firefox, just paste that code into their appropriate javascript console.

You’ll notice the iCloud interface is very iOS-like and all the animations and buttons feel like iOS, pretty impressive for the web wouldn’t you say?

This little tip comes from @devongovett via @viticci on Twitter, you can follow us there too.

Update: To clarify, most things don’t work without a beta login, and each time you click on something you will get an error message like the one below that requires you to reload the springboard again.

The final version of Xcode 4.1 has been released as a free download to everyone via the Mac App Store. Mostly for developers, Xcode is the Mac OS X-only development environment for creating OS X and iOS apps, but the package also includes various useful command line tools, and even an iOS hardware simulator, making it a worthwhile download for power users as well as developers.

Before you get the latest version of Xcode though, you will need to download Mac OS X Lion and complete that installation.

Get XCode 4.1 free from the Mac App Store

Here are the key changes for XCode 4.1 with Lion support, via the App Store page:

What’s new in Xcode 4.1 for OS X Lion
- Includes SDKs for OS X Lion and iOS 4.3
- Interface Builder support for Auto Layout and new Aqua controls such as NSPopover
- Full screen support in workspace, project, and organizer windows
- Project modernization to identify and resolve out of date build settings
- Behaviors can be customized and assigned to unique key bindings
- Source control enhancements to pushing, pulling, and management of remote servers
- Assistant editor support for display of generated assembly and preprocessed output
- Additional bug fixes and stability improvements

Prior to this release, Xcode cost $4.99 to download.