Why AdMob’s reported iPhone and Android market shares are inflated

AdMob, the mobile advertiser that was bought by Google some months ago, has released its latest market share figures for the mobile browsers.

Their main findings have already been discussed extensively:

  1. Smartphones are on the rise; 48% versus 35% last month.
  2. Feature phones are falling quickly; 58% to 35%.
  3. Still, the absolute number of feature phones rose by 31%, which means that the market as a whole is growing rapidly.

The AdMob report, however, is not about browser market share but about ad impressions. And that may matter a lot. Unfortunately we don’t know how much it matters.

Market share — of what?

Let’s go through AdMob’s careful methodology notes (last page in PDF; emphasis mine):

For every ad request AdMob analyzes information available in the user’s mobile browser [i.e. the user agent string]. From this, AdMob determines device capabilities and more using open source tools and a variety of proprietary techniques. The result is a snapshot of the devices viewing the more than 10 billion monthly ad requests and impressions that flow through AdMob’s network. [...] AdMob also serves mobile ads into iPhone and Android applications. The traffic from these applications is included in the Metrics report.

In other words, the figures AdMob gives are not pure browser market share figures. They include requests from apps that happen to have AdMob ads in them.

That’s vital (and it’s something that’s mostly ignored by other website that report on the AdMob stats). Let’s take a closer look.

  1. AdMob allows developers to deploy ads in their iPhone, Android, webOS, and Flash Lite applications. Thus, these browsers tend to be overrepresented in AdMob’s stats.
  2. From Adobe’s data we may draw the conclusion that Flash Lite is mainly supported by feature phones, many of them Japanese. The only partial exception is that it’s supported on some (but not all) Nokia Symbian smartphones. Thus Flash Lite ad impressions will not have a meaningful impact on the smartphone market share report everybody concentrates on, except a little bit for Nokia.
  3. That leaves iPhone, Android, some Symbian, and webOS. The latter’s market share is marginal; 3% in the US, “other” elsewhere (page 7 of PDF).
  4. Thus we’re left with all of iPhone, all of Android, and some Symbian.

I am forced to conclude that AdMob’s iPhone and Android figures are inflated. The true browser market share of Safari iPhone and Android WebKit is less than the AdMob report suggests.

All this is not AdMob’s fault, by the way. It’s being very clear about what it measures. Most analysts, interested only in the horserace between Apple and Google, tend to ignore that, though.

Exactly what is the inflation rate? How many iPhone and Android impressions are from apps, and how many from the browser visiting websites? We have no way of knowing. I’m not even sure if AdMob has any way of knowing.

If it does, I would like to request splitting out these figures. The AdMob monthly overview is one of the most important mobile browser market share reports we have, and any attempt to make it more precise will be gratefully received.


With all that said, what figures does AdMob report? It does not actually report browsers, just operating systems. Worldwide states, smartphones only:

  1. iPhone OS 50%; inflated; includes iPod Touch
  2. Android 24%; inflated
  3. Symbian 18%; slightly inflated
  4. RIM OS 4%; BlackBerry
  5. Windows Mobile 2%
  6. Other 2%

I find RIM curiously low. Of course the default BlackBerry browser is not very good, and that will certainly negatively affect its market share, but 4% is still very low.

An explanation might be that BlackBerry is now extremely popular among the youth, who mainly use it for chatting with their mates (as well as calls and SMS, obviously), but not so much for browsing.

Adjusted figures

Let’s try to adjust these figures. I’m going to make up numbers; feel free to make up your own.

I will assume that one third of the iPhone and Android numbers and about one ninth of the Symbian numbers come in fact from in-app ad impressions and do not count for browser market share.

  1. iPhone OS 45%; includes iPod Touch
  2. Android 22%
  3. Symbian 22%
  4. RIM OS 5%
  5. Windows Mobile 3%
  6. Other 3%

Not that much of a difference, although iPhone drops below the magic 50% and Symbian is now equal to Android.

US figures

Of course, pundits are mainly obsessed with the US figures. There is no world.

  1. iPhone OS 44%; inflated; includes iPod Touch
  2. Android 42%; inflated
  3. RIM OS 7%; BlackBerry
  4. webOS 3%; inflated
  5. Windows Mobile 2%
  6. Other 3%

Note that the iPhone share is smaller than in the overall world. Why? Does Europe have such a significantly higher iPhone penetration than the US? Or higher app use? I doubt it. But I have no idea what else could be going on.

Anyway, the story of the day is how Android is nipping on the iPhone’s heels, and that’s of course always good for a nice story. Do the figures bear this out?

It could be. After all, I assume that we can subtract roughly the same part from both OSs due to in-app ads. But, and that’s an interesting thought, might the rise of Android in the last six months or so be due to a significant increase in in-app ads, instead of web use and/or increasing sales market share? Have Android apps increased so sharply in the past few months? No way to tell.

Still, the overall take that Android is nipping on the iPhone’s heels in the US seems to be generally accurate. In the world as a whole, the effect is less visible both in absolute and in relative numbers.

To close off, let’s do the same random calculation as with the worldwide figures, and let’s assume that webOS impressions, too, are one third in-app.

  1. iPhone OS 41%; includes iPod Touch
  2. Android 39%
  3. RIM OS 10%; BlackBerry
  4. webOS 3%
  5. Windows Mobile 3%
  6. Other 4%

The main result is that BlackBerry’s share increases, and that’s something that I think is close to the truth. (Again, I’m guessing here. I could be totally wrong.)


Concluding, it is not really possible to draw meaningful conclusions about mobile browser market share from the AdMob numbers until AdMob splits them up into website and in-app ads. Be very careful in using these figures.

This is the blog of Peter-Paul Koch, web developer, consultant, and trainer. You can also follow him on Twitter or Mastodon.
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Comments are closed.

1 Posted by Pieter Bayens on 30 March 2010 | Permalink

The AdMob numbers are completely meaningless when it comes to mobile browser market share. Or internet usage on mobile platforms. The only thing these numbers tell is what AdMob's market share is in advertising on different mobile platforms. :-) It's a shame these numbers are often falsely interpreted as internet usage market share of mobile platforms.

Apart from that, I think you are right in 'adjusting' the numbers, but still, this is just a complete guess, not even an educated one. For the sake of this articles 'value', I suggest you either remove that part or make a calculator so people can play around with the numbers for them selves. ;-) Imo it doesn't 'add' anything to the conclusion. No flame intended of course - the basic outline of the article is something I completely support!

2 Posted by George on 30 March 2010 | Permalink

To help with some numbers, Android just surpassed 40,000 "apps" in their store. Now, the store does more than just applications (widgets, themes, etc.), but the sharp increase in the number over the last 6 months may also tie into the sharp increase in Android market share, especially given how most apps serve the ads up (embedded web browser).

Anyway, take the two cents worth of information and use it as you wish.

3 Posted by Marty Alchin on 30 March 2010 | Permalink

While I agree with the notion that the AdMob numbers are likely incorrect, I don't think it does anybody good to try to "make up numbers" and do "random calculations" to get what you believe to be more realistic results. If the point is to get accurate numbers from an authoritative source (which it sounds like it is), I can't imagine how imaginary figures would help. You're only compounding the problem.

4 Posted by Andrew Hedges on 30 March 2010 | Permalink

I think the reason pundits focus so closely on these numbers, and are therefore tempted to extrapolate from them, is that we don't have many good sources of data on browser share on mobile. What would be interesting to me, @PPK, is a proposal by you on how to gather better numbers in the first place.

5 Posted by Bob on 30 March 2010 | Permalink

"I know it isn’t the most accurate data out there, but directionally it speaks volumes about the market." - Om Malik

6 Posted by Lars on 30 March 2010 | Permalink

The main conclusion must be that Android and iPhone users desperately need Adblock.

7 Posted by Ndrw on 30 March 2010 | Permalink

Regardless of whether it is browser or app share, it is still significant that Android is catching up with the iPhone, however all that means is that the iPhone had the vast majority of the share before Android came along, so naturally is losing share from that as more Android phones come along.

Also, it is worth considering that for these numbers to mean anything at all, we are asserting that there is no favouritism of ad provider on one phone vs the other. i.e. Perhaps the iPhone has other alternatives while android phone app writers have less choice.

All in all, the graph doesn't really mean anything in a practical sense without working extremely hard to understand exactly what is going on.

8 Posted by Liam the lemming on 31 March 2010 | Permalink

I browse on an E71 under a 10MB/month tariff. (THE HORROR.) I'll be looking to go Unlimited Internet on my next contract...

Anyway, due to my limited data allowance, I browse on Text Only setting. No images, nothing. Just text. Well, and CSS, obviously.

That means no ads, doesn't it?

I wonder if they've considered that, and if/how it affects their stats.

9 Posted by Spudley on 31 March 2010 | Permalink

Completely unscientific but....

Where I work (in software development, in the UK), all the "in crowd" guys have IPhones, and are very happy to show them off to the world at the slightest excuse.

But I travel to work by train, and thus see a lot of people using their phones in a day-to-day environment where they're just using the device, not showing off. Virtually all these people seem to be using Blackberries.

My conclusions from all this are:
1) People who want to show off have IPhones. But these are the same people who will jump ship as soon as something else becomes the latest must-have toy. Android is starting to eat into this market, but IPhone still has mind-share.

2) People who just want to use the device day-to-day are opting for Blackberries.

In the UK, the Blackberry is by far the best value smart phone in terms of features offered vs amount you pay. The free email is a deal clincher. The salespeople never mention fact that the Blackberry browser sucks, so you only find that out once you've paid your money, and my guess is most people probably don't realise it even then; they just live with what they've been given.

Of course, as I said, it's totally unscientific. Just my personal observations.

10 Posted by Jason Grigsby on 1 April 2010 | Permalink

You should take a look at Millennial Media's reports for U.S. market.

They also show iPhone dominating, but the #2 manufacturer in their reports is Samsung.