By Brenna Hanly

With all of the fanfare around mobile, Apple versus Google, the iPad replacing the PC and the allure of the iAd platform, I thought it may be appropriate to write a piece about the basics of buying mobile media. 

That is exactly what this article is about ? tactical but critical approaches to buying mobile media. Some considerations:

Step 1: Why are you buying mobile media?
Know the goal you want to achieve through purchasing mobile media.

Is it to drive application downloads? Convert sales? Build on long-term branding?  Depending on your strategy, you will want to buy mobile media differently.

Step 2: Who should you buy it from?
There are many different players to consider when purchasing mobile media. 

Like digital, there are hundreds of mobile ad networks and lots of publishers. The major mobile ad networks are Millennial Media, Jumptap, Apple iAd (formerly Quattro) and AdMob (acquired by Google). 

If you are conducting a direct response campaign, you will likely want to work, at least in some part, with the networks. 

For a more custom and, frankly, more interesting campaign, you will want to work directly with the publishers and build something together through kitchen-table planning.

Step 3: Which network partners should you choose?
If you choose to use ad networks, you will want to test a couple of different networks and then based on mid-campaign results, optimize out of underperforming placements or networks as a whole. 

Some differentiators between networks include targeting capabilities, scale, exclusive inventory (on-deck), rich media considerations and blind versus open. 

For instance, the iAd product/network has unique targeting capabilities because it can tap into the Apple iTunes data and target based on music preference. 

However, the networks will not guarantee impressions or tell you where your ads are running.

Be sure to understand the capabilities with regards to the above considerations before buying media. 

Step 4: What is the pricing structure?
In most cases, mobile media is bought on a CPM basis. However, this can vary and many of the blind networks can be purchased on a cost-per-click basis.

Step 5: How is it performing?
Mobile media should be monitored regularly, not just when the campaign is over. 

You will want to be evaluating and optimizing throughout to obtain the best results to meet your initial campaign goals.

The above represents some of the staples that we use to determine how and where to buy mobile media. 

As the mobile landscape continues to evolve, it is important to be at the forefront of new opportunities, but also be cognizant of the blocking and tackling to ensure the success of your program. What additional key considerations are your agencies or teams deploying? 

Brenna Hanly is mobile catalyst at Boston agency Mullen?s mediahub. Reach her at .