A new study from eMarketer predicts mobile advertising will generate $1.23 billion in the United States this year.

The forecast also expects mobile advertising in the U.S. to reach $4.4 billion by 2015. The growth comes as mobile advertising gains steam as an effective way to target consumers thanks to the growth in smartphone and tablet ownership.

?Although our forecast calls for incremental raises for 2011, it is setting up for steeper growth for mobile advertising in 2012 and beyond as tablet and smartphone adoption ramps up quickly and more people access the Web from these devices,? said Noah Elkin, principal analyst at eMarketer, New York.

Interactive advertising
In addition to the projected numbers for 2011 and 2015, eMarketer expects that mobile advertising will continue to increase across all channels.

For 2011, messaging will rake in the most ad spend with $442.6 million.

In second place, banners and rich media will account for $376.4 million in 2011.

Search will make up $349.4 million and video will bring in $57.6 million.

?As more people use these devices and as they are a more central part of how people access content, it becomes more imperative for marketers to focus on mobile,? Mr. Elkin said.

?The key is to make consumers see mobile ads as useful,? he said.

The report predicts that banner and search ads and search will account for a majority of ad spend in 2015.

In 2015, mobile search advertising is expected to account for $1.7 billion, and banners and rich media will account for $1.6 billion.

Grow on mobile
While the growth in mobile advertising is exciting prospect, marketers should keep the numbers in perspective. They should also think about the long-term results of mobile advertising by using Web advertising as an example.

U.S. mobile ad spend generated $743 million last year.

?Taking into consideration the evolution of online advertising, as consumers become more accustomed to seeing mobile ads, they could become less effective,? Mr. Elkin said.

?In terms of how advertisers can avoid this inevitable decline, they can focus their energy on the formats and media buys and maximizing what you can get from search and what you can get from advertising,? he said.

?It is possible that as people become more accustomed to seeing ads, consumers will regard it as useful.?

Final Take
Lauren Johnson is editorial assistant on Mobile Marketer, New York