Back in May we showed you how iOS was losing some ground in the mobile operating system fight based on a report from Millennial Media.  That data covered the month of April.  The data for May (PDF link) showing that iOS had lost another 14 percent, and the majority of that loss going to RIM’s BlackBerry OS and Google’s Android OS.  Apple fell to 48 percent of the market, and things were looking a little shaky for the company.

And then the data for June (PDF link) hit, and isn’t it amazing what a new phone can do for you?

Mobile OS mix for June 2010

I am not a big fan of looking at data that is only shown as percentages, it’s just too easy to go “Oh HO!  See that massive jump!” when it could be any number of raw data manipulations.  we are also talking about data based on Millennial Media’s ad impressions from apps.  While the company is one of the leading ad sellers for mobile apps, it is well known the iPhone has the most apps, and in turn that easily skews market share when you are discussing operating systems.  And in the above graph, they are also counting in the iPad (which they say grew 206 percent month-over-month) and the iPod Touch, so don’t think this is just talking about iPhones.

The main piece of data I do find interesting is that while Apple continues to rule the roost using these metrics, Millennial Media has still seen a jump of 439 percent in the Android ad impressions since the beginning of the year.  Again, without raw data, that could mean it went from 1 impression to 439, you just don’t know.

Is there any way to tell who really is winning the cell phone wars?  Is there any true test if Android is catching up?  Sure there is, but that would require companies to release hard data of not only how many handsets are sold, but how many are currently active at any given time.  Just because Google goes around saying 65,000 Android handsets are activated each day, it doesn’t mean that it’s 65,000 new users because for all we know it could be 65,000 replacements of existing handsets.  I doubt that it is, but how do we know?

It’s always fun and interesting to look at this sort of stuff, but I always suggest taking it with a grain of salt.

What say you?  Do you wish there was some better, and truer, test of how each cell phone OS was doing?