It's another sign that mobile is the wave of the present, not the future. According to the Interactive Advertising Bureau, spending on mobile advertising it taking off like a rocket. As the Wall Street Journal reported, mobile ad spending in the first half of 2013 hit an estimated $3 billion, more than double the $1.2 billion in 2012.

For big companies, such as consumer products giant Unilever and food brand company Mondelez International Inc., mobile is no longer an experiment. But that doesn't mean entrepreneurs should jump into sending money into mobile marketing. A big company can dump a lot of money into an area and barely feel a twitch. You need to make your spending count.

Advertisers had held off from mobile marketing in the past because of perceived problems with technology and measuring audiences. For example, how do you deal with fragmented platforms, the fractured nature of Android and its many versions, and knowing how many people on a mobile device actually saw that post in their Facebook or Twitter timestream?

How to Get Started

First thing is to realize how many different types of mobile marketing there are, which leverage particular strengths, how flawed they can be, and how you must learn to work within the limitations. The biggest name in mobile ads remains Google. When you consider that Android has about 80 percent mobile operating system market share, you can see why. This is the reason that the company bought the original Android developer and has continued to put money into it.

According to the Journal report, eMarketer estimates that Google will have almost 47 percent mobile ad market share this year, largely due to search ads. That means don't just consider where you will run ads, but whether you have a coherent mobile communications strategy, including mobile-friendly websites as well as social. No sense in getting someone's attention if you're going to drive them away quickly.

Twitter is going great guns. But as I've mentioned before, not all its main ad programs work equally well on mobile. Two of the company's big marketing options--promoted trends and promoted accounts--"receive less prominence" than on browser versions of Twitter. You might want to focus on promoted tweets, instead, which show up the same way on mobile

Facebook, is pushing heavily in mobile because so many of its users connect from its apps. Because of the app layout, an ad should show up in the middle of what consumers are reading. And yet, many advertisers are displeased with the systems. They may have problems with using the ad tools themselves.

Some portion of the problems likely belong to Facebook, but there is also a good chance that some marketers either don't pay enough attention to the documentation on tools or fail to grasp the explanations. In that case, they should ask questions or find some professional help to guide them through the process. Even if the mechanisms are confusing, someone has probably figured out how to make them work.

No matter what road you take, write a good mobile ad. You'll have less visual room than usual. Does you ad lend itself to a touch user interface response? Is the use of words efficient?

Mobile is absolutely an important area for startups, entrepreneurs, and marketers. Make sure you do your homework, spend efficiently, and enable a prospect's response to deliver what they're looking for.