Apple iOS Developer Program: If you want to publish your own apps to the App Store this is where it all starts.

Apple’s iOS Human Interface Guidelines: Read them. And then read them again. Even though they are geared a bit more toward productivity and utility apps for adults, there are lots of insights on how to design effective interfaces for mobile.

Overview of iOS Game Frameworks: A good introduction to the variety of frameworks available to take some of the pain out of creating your own apps.

Do I need to know how to program to do game design? An excellent response to a frequently asked question.

Inventing (Playful) Invention: Great overview of the process of creating digital play experiences for kids from the creators of Toontastic.

User testing at zinc Roe: Notes on how we approach user testing with kids. Some important considerations here to ensure you get useful feedback.

App Licensing: An excellent blog post from Night and Day studios on how they went about entering into licensing deals. Moms with apps is a loosely-organized group of (mostly) indie developers building apps for kids. Their forums are a great place for creators who are just starting out.

There are a lot of good kid app developers out there, here are a few of my favourites:
Toca Boca
Launchpad Toys
Kidoodle Apps
Duck Duck Moose
Night and Day Studios
Crab Hill Press
Nosy Crow
Gareth Lancaster
Matt Hammill

The zinc Roe team comes from a very diverse background in terms of education and work experience. We value portfolio and personality above all other considerations. Show us what you’ve built. Tell us how you built it and why.

There are two things that make localization of children’s apps different than typical apps. First – including assets for multiple languages in a single app means each additional language can result in much bigger app files sizes. This is because children’s apps often include a lot of voice over. Second – users may want to switch back and forth between languages frequently. In traditional apps users are more likely to use the app in their native language and stick with that. With children’s apps parents often want to have their little ones play in multiple languages as a way of improving their language skills.

1. Publish two separate apps

The advantage here is that the apps are smaller in size (no need to include localized versions of all the assets. Also, everything about the app from the search-engine-friendly URL in the app store to the app name and content is in the native language making it fairly clear when promoting the app in different languages. Even if their device is set up in English you can send them to a URL where you can be sure they will see the French app name and description in the app store. The downside is that families who want their kids to play in both languages have to buy the app twice. It also means maintaining two apps so QA and updates can take a bit longer.

2. Publish one app and build a language setting into the app

The advantage here is that parents and kids can fairly easily switch back and forth between languages. File sizes grow because you need to include assets for both languages. In apps like Stella and Sam that means duplicate copies of audio files as well as all the graphics used in menus. The big disadvantage though is there is no way to localize the app name on the device. The books and the tv show have a significant audience in France and French Canada and Stella and Sam is actually Stella et Sacha in French. So promoting a ‘Stella and Sam App’ and then relying on native French speakers to navigate to the appropriate setting is less than ideal.

3. Publish one app and rely on the device’s language setting

Apple’s development tools include a fairly elegant method for supporting multiple languages within a single app. File sizes are still big but following this approach means that everything from the app’s name on the device right down to the graphics assets are set based on the language setting on the device. This is the method that Apple recommends but it’s designed more for localizing an app like Safari than it is for a kid’s game or storybook. For native French users this gives the same advantages as #1, namely that the entire experience from end-to-end is in French. The big downside is that users who want to switch back and forth need to navigate away from the app to the Settings App to switch languages and then come back to the app.

The File Size Issue

As I’ve mentioned, embedding assets for more than one language can result in very large file sizes. The Stella and Sam Apps include 2.5 minutes of high-quality video and two sets of videos would have pushed our file sizes from about 60MB to around 100MB. Based on a suggestion from an Apple engineer at WWDC we looked into building an app that would download these large assets on the first run. But after looking into this we opted against the idea for three reasons: extra development and QA time to build a thoroughly-tested system for managing the download process, a long delay when the app is first launched and the assets load, and frustration and disappointment if parents first launch the app while offline. Although we embedded all the assets, we were able cut down on file size by separating out the audio tracks from the video. Since only the audio is different we embed one video track and two audio tracks. Based on the language settings we play the appropriate audio track and sync it up with the video.

Conclusion

As a parent, I love the idea that kids can hear the story and play the activities in both languages as a way to re-inforce their language skills. As someone who has worked with software for non-English users I also understand how important a seamless native-language experience is to having legitimacy in these markets. Making the decision was difficult but in the end we chose #3. It allowed us to publish a single app while offering a completely French experience right down to the app names. Also, following Apple’s recommendations generally means fewer surprises down the road.

So far I’ve had one support email asking about how to switch languages and one bad review from a user who was clearly unaware of how to switch languages. As we anticipated, this solution is not ideal for parents who want to switch between the languages frequently. However, for native speakers it has worked tremendously well. Apple featured the Stella and Sam Apps in both the Great Canadian Apps and Apps en Français sections.

Final Tip

One issue we ran into was how to link French-Canadian users to the App in iTunes without displaying the preview page in English. If we used the link as provided from Apple it would display the English preview page. Unable to turn up anything in Apple’s docs I started playing with the URL and discovered that adding a ‘&l=fr’ to the end of the URL forces the display of the French app details on the preview page.

Candidates must have
• Hands-on experience with game development for the iOS platform.
• Proven experience with XCode, Obj-C, and related technologies.
• Solid understanding of fundamental programming concepts.
• Experience preparing and compressing audio and visual assets.
• A hungry mind eager to learn new skills.
• Good verbal and written communication skills.

Experience with Cocos2d, box2d, openGL and Adobe Flash are not required but would be a definite asset. We promise a rewarding job working on creative projects for kids with some talented folks. This is a full-time position based out of our office in downtown Toronto.

zinc Roe is an award-winning studio specializing in creating engaging websites, games and activities for kids and youth. Our goal is to raise the bar for quality interactive media for children. Our clients include Teletoon, Playhouse Disney Canada, Toronto Public Library and the 2010 Winter Olympics. Take some time to browse our portfolio and learn about the kind of work we do. As long as you have enthusiasm and sound technical foundation we are happy to provide opportunities for the right candidate to pick up specific skills.

Please send a resume and include details of recent projects to jobs *at* zincroe.com. Do not call. No recruiters please.

To get your free app just look for the ‘redeem’ link in iTunes and enter one of the following codes. To save others from wasting their time with codes that have already been used please leave a comment with the codes that you’ve used.

UPDATE: It looks like all the codes have been used. To find out about future giveaways sign up for our newsletter or follow us on twitter!

Enjoy!

Sound Shaker
3NKFYHJEMFHE
JM4KHL67FY3R
RRMRPYFAYX9F
43LKLWJYYJLT
A9AMR4PHLEWJ
WPX7YF6JM4AH
JWFFRYK7KE79
WW3MTFNR7MTK
XM3MLP4LKWPM
MEREENFEKLEY

Sort Slider
7FL9AW6944R9
MYTER6MF6HEH
6R369PA6XHTP
WHJPLMYX3HT6
Y99MN6343LHY
F3AFTAN3WN3T
767YL9WALWK3
NA4HTLK99HML
96JFRETW3A3A
YNF4F9KFPN99

Bug Builder
3EEKHK34AXRJ
KNPHJRJHAY4F
H9WHYT4AHM6E
7RLF9WTF4T9W
MKW73PLRAAAP
XEW4RPF6TKKF
NE7XT674WMY4
JPLYXF37EWFW
YWMP3ERRFNL6
RK4XW4HNXTYN

Tickle Tap Apps kicked off with a pitch written back in early 2009. At the time zinc Roe had produced only a couple of iPhone apps and had never designed preschool content based on a touch interface. We dug deep into our own pockets to finance the project and it was the first where we were selling content directly to parents.

Sound Shaker launched in November 2009 and in the year since then we’ve launched a total of ten individual apps along with the two bundle apps. This project embodies much of what I love about zinc roe. We dove into unchartered territory, learned as we went and discussed and debated everything from the merits of openGL to how four-year-olds held iPhones. Some apps ideas progressed smoothly. Others veered all over the place before we got them on track.

The apps have had an overwhelmingly positive response from parents and kids. And the story is much the same in the industry. We’re learned a great deal through our work on this project. The exciting news is that while Tickle Tap Apps is winding down we have some really fantastic new kids iPhone projects to apply all that we’ve learned.

We have a great team who made this project happen. All of us want to thank our colleagues for their advice and support and the parents and kids for their feedback and encouragement.

We ran numerous testing sessions with kids throughout the development of our apps. Many very informal with friends, family and a few strangers here and there. With the help of mom and HCI consultant Deborah Ptak who works at University of Toronto we were able to gather a lot of useful feedback on the apps. Deb organized and ran a number of testing sessions with kids aged 3 to 6. We were able to make quite a few small improvements based on these sessions. Many of these issues can be grouped into three sets:

Unintentional triggering of the buttons. Any buttons near the edge of the screen WILL be hit by kids by accident. Repeatable. The Tickle Tap Apps use a ‘back’ button placed in the bottom right corner of the screen (all our preschool apps are landscape). Over and over again we watched as kids accidentally hit this button as they shifted their grip on the device. As a result we moved the placement of this button to the top left corner. So keep your buttons away from the edges of the screen and especially the bottom corners of the screen. And when it comes to do QA testing make sure your app survives all ten fingers mashing madly away at once.

Unintentional touches blocking intentional touches. Unless you make special accommodations an active touch event will block the triggering of subsequent events. In other words if you are touching the edge of the screen accidentally the app won’t respond to intentional touches. A solution is to set up your apps as multitouch and write the code in such as a way the it can accept input even if a stray finger is resting somewhere else on the screen.

Voice-over and animation overload. This came out only after longer game-play. Once kids got the hang of a game they charged ahead and suddenly the voice-overs went from helpful to annoying and the animations from novel and rewarding to just getting in the way. So we got smart with our voice-over. We took some of it out, we made some of it play only after an inactivity time-out and made some of it only play the first time through on a new game play. And we pared back the frequency of the little animations that are peppered throughout our apps. Getting this balance right is tricky and of course it’s not an issue that is limited to mobile apps.

So I hope all the AppCampers enjoy the Ocean views. Building apps for kids has been a tremendous experience and I’m sure I don’t need to tell you how liberating it is to break out of the browser and ditch the mouse and keyboard. Consider this an open invite to get in touch and share your questions and insights. Tickle Tap is just the start for us!

The YouTube player breaks Sound Shaker because the app recieves an audio interruption event (kAudioSessionBeginInterruption) when the YouTube player opens, but never receives a corresponding event (kAudioSessionEndInterruption) when the player closes. Being a good citizen, the app deactivates it’s audio session (and suspends it’s OpenAL context) when the interruption begins, but the poor little guy never gets a chance to reactivate it again. Not cool.

The YouTube player breaks Field Flier because it creates a new key window when it opens and sets the key window to nil when it closes. When Field Flier goes looking for the key window, it’s nowhere to be found. Oh sure, the app could listen for a UIWindowDidResignKeyNotification notification to reset the key window – too bad the YouTube player doesn’t trigger that particular notification. I’m pretty sure the YouTube player has it’s thumbs in it’s ears going na nana nana na at this point. Again, not cool.

The hacktastic solution to both issues is to listen for a UIWindowDidBecomeVisibleNotification notification on the app’s main window and manually call the interruption listener callback and reset the key window. I put the relevant code in the app delegate, but if your app shows and hides the main window for some other reason, you’ll probably need to get a bit fancier.

Here’s the relevant code in TickleTapToddlerPackAppDelegate.m:

void interruptionListenerCallback (void *inUserData, UInt32 interruptionState ) {
  if(interruptionState == kAudioSessionBeginInterruption) {
    AudioSessionSetActive(NO);
    // suspend OpenAL context here...
  } else if(interruptionState == kAudioSessionEndInterruption) {
    UInt32 category = kAudioSessionCategory_MediaPlayback;
    AudioSessionSetProperty(kAudioSessionProperty_AudioCategory, sizeof(category), &category);
    AudioSessionSetActive(YES);
    // resume OpenAL context here...
  }
}

- (void) applicationDidFinishLaunching: (UIApplication*) application {
  // initialize the audio session and register the interruption listener callback
  AudioSessionInitialize(NULL, NULL, interruptionListenerCallback, self);
  UInt32 category = kAudioSessionCategory_MediaPlayback;
  AudioSessionSetProperty(kAudioSessionProperty_AudioCategory, sizeof(category), &category);
}

- (void)didReceiveWindowDidBecomeVisibleNotification:(NSNotification *)notification {
  // manually call the interruption listener callback
  interruptionListenerCallback((void *)self, kAudioSessionEndInterruption);
  // manually set the key window
  [self.window makeKeyWindow];
}

Why would a three-year-old want to play games on an iPhone? Actually, let’s re-think that—why wouldn’t a three-year-old want to play games on an iPhone?

iPhones and iPod Touch devices are extremely attractive to small users in the three- to five-year-old snack bracket. These devices are easy for small hands to use—much easier than computers, keyboards and mice. Children can also use them anywhere. Think of the possibilities: while waiting in line with you, while traveling or commuting, in the car, during quiet moments at home. Anytime your child is looking for an activity. Anytime you’d like your child to be engaged and interested instead of frustrated or bored and distracted.

But if you’re going to hand over your iPhone or iPod Touch to your child to play with, you’re going to need some entertaining apps for him or her to play. That’s where Tickle Tap Apps come in. Tickle Tap Apps are age-appropriate educational games that encourage learning through practice and exploration. They take full advantage of the iPhone platform in ways that make game play exciting. They’re also easy to use, with audio instructions and visual cues so preschoolers can pick them up and start playing right away.

The first three Tickle Tap Apps will be available very soon from the iTunes App Store. Visit TickleTapApps.com to learn more. Plus get sneak peeks at game play by watching demo videos of Sound Shaker, Count Caddy and Sort Slider.