The charts show how iTunes content revenue has been steadily growing upward and to the right. But they also show that Apple saw an increase in iTunes net sales by $300 million just from the holiday quarter (when Apple always sees its biggest concentrated pop in downloads) to the March quarter, making $2.4 billion in sales. This is also up from $1.9 billion during the same quarter a year ago.

Relatively, this is still very tiny compared to the $23 billion in net sales Apple derived from its most essential business, the iPhone. And to the $8.7 billion from the iPad last quarter. But iTunes alone is close to half of Mac net sales, which were $5.4 billion.

The reason for the increase is mostly due to Apple’s steady expansion of the iTunes Store to new countries around the world in recent quarters. iTunes Music sells in 119 countries, videos in 109 countries, while the App Store and iBookstore are both in 155 countries.

According to Asymco’s calculations, this wider availability in the store has driven up the amount the average user is paying Apple for content:

In March Apple reported that they have 500 million iTunes [users] so one way to think about the iTunes business is to say that  iTunes users purchase content and services at the rate of about $40 per year.

This is really interesting in the context of the long-rumored Apple video subscription deal and the still-being-hashed-out “iRadio” service for subscription music content. Imagine if just in just some of those countries Apple introduced a $10 per month streaming solution. So instead of $40 per year from a user, Apple started getting more like $120 per year. And that would be just music. If there was a separate video package some day that figure would get even larger. Plus, that doesn’t include money spent on and within both Apple’s own iOS and Mac apps and third-party apps.

iTunes has always been more of a bonus source of revenue than a meaningful contributor to Apple’s bottom line — the songs were originally there to sell iPods, in the way mobile apps are there to sell iOS devices. But software and services — from iCloud and Maps to Siri — have begun to play a more prominent role at Apple, and in its customers’ experiences. A subscription service of digital content, if deployed and priced correctly, could actually turn into a meaningful new source of revenue for Apple.

If current trends continue, with software and content sales going up and laptop and desktop sales dropping off, it’s not impossible that Apple’s content business could someday soon outpace the Mac segment as its third-largest business.

The app has a customized, scrollable feed of the latest news stories that are relevant to your device. If you click on a story, say a review of Twitter’s new iOS Music app, Drippler inserts a link to the app at the bottom of the screen. If you click install, it leads you right to the App Store.

The items that appear in your Drippler feed are crowdsourced — if other users similar to you like the stories, they’ll appear in your feed. As you click on items, download apps or “like” content, Drippler’s algorithm will get better at determining what is and is not interesting to you. If you’d rather not have to scroll through the Drippler feed every day, you can opt to receive “daily drips,” which are personalized items that arrive via a push notification once a day.

Android first

Drippler is one of those rarities: an app that started out and gained its popularity on Android before landing on the iOS platform; in the last year it’s racked up 5 million downloads in the Google Play store. CEO Matan Talmi told me last week that route was necessary because of his core audience. “We started on Android because [the app] is device-specific, and there are more Android devices” in his company’s home country of Israel. “But now we have to be on iOS,” he said.

The goal is “to make the iPhone better for mainstream users,” Talmi said. In that case, his timing isn’t bad. Apple has entered a new era of the iPhone — one where more than ever it’s putting older, discounted iPhone models in the hands of customers who’ve never owned a smartphone before. It’s these kinds of customers — the opposite of early adopters — that may benefit the most from a personalized service like Drippler.

MoPub Mobile Advertising Marketplace Report Q1 2013

MoPub, which is an ad-serving platform for mobile app publishers, found the iPhone was the strongest performer during the quarter; the report says the share of ad buying on Apple phones increased 12 percent between January and March. The iPad experienced a drop-off in spending in February but rebounded a bit in March.

The share of Android tablet spending was negligible at less than 1 percent, according to MoPub. Android phones, which took about a quarter of all mobile ad spending, saw the reverse pattern from the iPad: spending on the platform increased in February before dipping back down in March. MoPub explains that “In Q1 2013, many ad buyers discovered the increase in user value on Android devices was offset by a poor conversion rate of users from these ads.”

As for the kinds of ads being placed, things swung more toward interactive ads, with the share of spending on them growing from 15.7 percent to 79.1 percent during the quarter.

At paidContent Live 2013 Wednesday, Prismatic co-founder and CTO Aria Haghighi said those in the business of helping readers discover new content can’t even agree on a definition yet. “We don’t all agree on what personalization means. I agree (that it means pointing you to) stuff you care about … some people think it’s only getting signal from noise,” he said. “I think we’re really early. I don’t think we’ve matured to point where we (the industry) have philosophical differences yet.”

Mark Johnson, who is CEO of competing product Zite, agreed that there’s so much more to do. “We’re good at finding stuff, but we can be so much better. We haven’t had that Google moment yet that’s, ‘Aha! That’s what personalization is.’” He compared it to when AltaVista users turned to early Google search and said, “So that’s what search is!”

That point of personalizing reading content for users is also the challenge: everyone’s feed will always be different because no one likes the same stuff. Improving that capability will depend on big factors that haven’t quite been figured out yet either: the social aspect and helping people understand why content is recommended to them.

Both Prismatic and Zite agree that helping users understand why you’re showing them content is key: “Even if you do world’s best job recommending an article or content to people, if they don’t have an explanation of why, people feel uneasy,” said Haghighi. “You have surface parts of the system to give information to people. That’s where user response intersects with AI.”

Part of recommendation is social — what your friends or people with your same interests liked — but no one has done a good job of that in their industry yet, Johnson thinks. Social “sharing is the tip of the iceberg,” he said. “There’s something deeper you can do in these applications that no one has nailed yet.”

Check out the rest of our paidContent Live 2013 coverage here, and a video embed of the session follows below:

A transcription of the video follows on the next page

Go to page 2 (of 2) on paidContent .

The company hopes Marketplace will stand out because it is offering app publishers and developers a way to sell their ad inventory while also giving them accurate data about their audience. Flurry’s audience data is the big draw: the company said it has access to information about 300,000 apps used on over 1 billion devices. Flurry claims to have access to the user habits of 90 percent of all active smartphones and tablets in the world.

The idea is that if publishers understand more about who is using their apps — like parents or college students, for example — and why, they can make better decisions about where to place their ads in real time.

There are other real-time exchanges for mobile app publishers — like MoPub and Nexage, for example – but those still need outside user data to know how to target your ads.

Marketplace is the latest in Flurry’s effort to expand its capabilities to be a one-stop shop for serving app developers and publishers. Late last year it raised a $25 million dollar funding round, and already this year it launched one new product, a free crash reporting tool for app makers.

The league has offered mobile apps for several years and has continued to attract new app users each season by experimenting with pricing structures, adding new features and most importantly, giving fans ways to access its live and archived content on a phone or tablet. The audience has historically been made up of mostly iOS users, who account for 70 percent of the free At Bat app downloads and 85 percent of the paid app downloads. But MLB’s Advanced Media office, which develops those apps, says Android use has been growing recently.

Baseball’s mobile app audience is interesting because it’s not like the TV watching audience — MLB apps are not just used by fans who aren’t at a game. MLB has deftly built its online and mobile viewing audience by understanding that and embracing the ubiquity of mobile devices. MLB Advanced Media CEO Bob Bowman — who will be speaking at paidContent Live 2013 this month in New York City — told me recently that for younger fans, the smartphone “is the first screen, not second screen” and that any app the league makes “has to have everything” if they want to engage and keep those fans around for years.

Today MLB apps can be used as a mobile baseball ticket, and to check in, get coupons for merchandise, order food and even upgrade your seat during the game with MLB mobile apps — and, of course, to watch or listen to games when you’re not near a TV.

The report by Kantar Media also found that Samsung outspent the company it frequently mocked in its ads: Apple. The iPhone was the best-selling smartphone in the U.S. during the last three months of the year after the iPhone 5′s launch, but Apple didn’t increase its spending nearly as much in 2012 as its rival did. Kantar reported that Apple spent $333 million on iPhone ads in the U.S. last year, up from the $253 million the company spent the year before. HTC, which was third behind Samsung, spent $46 million, followed by BlackBerry, which spent $35 million, and Nokia, which spent $13 million on U.S. ads.

Samsung clearly has a lot of money to spend and it spreads it around too: The Wall Street Journal, in talking to unnamed wireless carrier executives, found that Samsung also helps to foot some bills for its strategic partners:

The heavy ad spending is only the most visible of Samsung’s investments. Some wireless carrier executives said the South Korean company also spends more on “below the line” marketing than any device maker. Those funds help pay for in-store advertising, promotions and training for carrier sales representatives that help close the sale.

The discrepancy in spending between the only two companies who are making any money at all in smartphone sales wasn’t just in quantity of dollars spent. In terms of quality, Samsung’s television advertising got people talking, especially “The Next Big Thing” ads that poked fun at Apple’s typically long lines on iPhone launch days and the people who wait in them.

Apple, meanwhile, had an ad campaign that got people talking in 2012 (remember the “Genius” ads?) — but for another reason: for how surprisingly un-Apple-like they seemed in quality of execution and tone.

The move was foreshadowed earlier this year. Both The Nikkei in Japan and AllThingsD reported in early January that Apple had signed distribution deals with three big Japanese publishers.

In a press release sent out on Tuesday evening Eastern time, Apple notes that the Japanese iBookstore features “titles from major and independent publishers, including a great selection of books from Kodansha, KADOKAWA, Bungeishunju, Gakken and Gentosha. The iBookstore has a wide selection of emerging and established authors including Shyotaro Ikenami, Jiro Akagawa, Atsuko Asano and Ryu Murakami.”

The Japanese iBookstore is also offering enhanced ebooks and “digitally exclusive titles including Ryu Murakami’s fiction novels ‘At the Airport,’ ‘Exodus of Middle-School Students’ and ‘I’ll Always Be With You, Always’  which has interactive emails in each chapter to bring you even deeper into the story.”

The update notes for 3.1 say, “The iBookstore in Japan now has hundreds of thousands of books available for purchase, including fiction, manga, light novels and more.” In addition, the update says there are reading improvements for “a number of Asian languages,” though the specific languages are not specified.

The iBooks update is out now and can be downloaded via the App Store.

This post was updated at 8:17 p.m. ET on Tuesday, March 5 with additional details from Apple’s press release about the iBookstore’s launch.

After fielding complaints from users of its iOS Kindle app of reset reading settings and missing books following an update, Amazon is now cautioning its iOS users against downloading the latest software update to its ereader app.

TUAW spotted the warning from Amazon Wednesday morning. Amazon posted a note on the app’s page in the iOS App Store that read “There is a known issue with this update. If you are an existing Kindle for iOS user, we recommend you do not install this update at this time.”

Complaints lodged by users who downloaded the update include one who said the “upgrade erased all content on my iPad, including all of my bookmarks” and another who said the “update deleted all books from my iPad, and I had to register again, creating a second name for the same iPad. It’s like starting all over again. Now I have to upload over 130 books from the cloud.”

The teams that will start accepting Passbook tickets for the first time are the Minnesota Twins, Baltimore Orioles, Milwaukee Brewers, Oakland A’s, Pittsburgh Pirates, Detroit Tigers and Chicago Cubs. The New York Mets, San Francisco Giants and Kansas City Royals, which began accepting Passbook last September, will again offer the service this season. MLB says there are three more teams that will enable iOS tickets this season, but that are not yet ready to make an official announcement.

MLB was among Apple’s first launch partners for Passbook, which went live with iOS 6 when it launched in September. That surely wasn’t a surprise to baseball fans who know MLB as the most tech-savvy league of all major professional sports. Major League Baseball’s Advanced Media Office, which is the digital arm of the league, responsible for MLB.com, MLB.TV and the At Bat apps, is run by CEO Bob Bowman — who’s speaking at paidContent Live 2013 in April. Bowman has made MLB a frequent and early partner of Apple when it’s come to mobile tech.

Last week, MLB debuted the 2013 edition of its At Bat app for Android and iOS, which included more live, archive and embedded video content, and a new deal to include free game audio access.

He stays ahead of the tech curve by trying to anticipate what the next generation of fans — the kind that grew up with ubiquitous internet access — will want in a mobile experience and how they prefer to interact with their team. The smartphone “is the first screen, not second screen” for them, he told me Tuesday. That means a mobile offering “has to have everything. [The app] has to be slick. If it isn’t hip, cool and easy to use, [fans] are not going to use it.” That’s why “everything we write and plan this is on the first screen.”

That includes using your phone instead of a piece of paper to get into a game, as well as using it to sort stats or watch classic video. But MLB’s mobile efforts are not all iOS all the time. MLB At Bat is also on Android, a platform Bowman said is growing rapidly for MLB.

Right now, he said, iOS users account for 70 percent of the free version of At Bat. But that’s “shrinking every day” as Android has grown — he says thanks to Samsung’s good mobile hardware and its growing cool factor, as well as the Google Play store being better curated by Google.

However, when it comes to users that pay for At Bat — which is $20 per season — 85 percent are still iOS. But that’s changing too, he said. “Slowly.”