The number of mobile Web users increased by 4 percent to 69.6 million in the United States in January, according to Millennial Media?s SMART report.

The increase is up from 67 million users and Millennial Media?s unique audience reach increased by 6.88 percent in January, from 54.3 million to 58.1 million unique users month over month to an 83 percent reach of the mobile Web. In addition, there was a third-party study conducted on the growth of mobile fundraising and its audience?s demographic.

?We have seen data that indicates the mobile Web is much larger than approximately 70 million users, but since we?ve been reporting the Nielsen data for the past 11 months, we can at least watch the trendline,? said Mack McKelvey, senior vice president of marketing at Millennial Media, Baltimore, MD.  

?The good news is that the mobile Web increased by nearly three million users month over month,? she said. ?We watched user session times increase from 4:57 in January, to 5:14 in February ? the longest session time we have seen since the June 2009 SMART."

Millennial Media is a mobile advertising company. Its SMART (Scorecard for Mobile Advertising Reach and Targeting) report delivers monthly insights on key trends in mobile advertising.

Here is SMART's mobile campaign quick stats:

Fundraising study
A joint study by Convio, Edge Research and Sea Change Strategies analyzed findings from a national survey of U.S. charitable donors that was conducted the week after the earthquake in Haiti occurred.

The study shows the power of mobile technology and trends among different demographics in advertising.

According to the research, prior to Jan. 12, more than $1 million had been raised via mobile text and $50M has now been raised via mobile in the aftermath of the earthquake in Haiti.

?We found this study timely to include in February?s SMART as it showcased the power of mobile technology and trends among different age demographics in a new and growing advertising vertical ? mobile cause advertising,? Ms. McKelvey said.

?We have been actively promoting causes via mobile for more than six months, including Estée Lauder's Breast Cancer Awareness Campaign and Ogilvy and Mather?s Hopenhagen campaign supporting climate change initiatives,? she said. ?Most recently, some of our key publishers donated tens of millions of impressions and we ran ads promoting the Red Cross, Yele and the MTV Hope For Haiti Telethon campaigns.

?Consumer interactions with mobile cause advertising are very similar to branding campaigns?this is exciting news for the non-profit sector.?

Here are special section mobile cause marketing stats:

Mobile apps
Additionally, application download demonstrated its third consecutive month of growth with 19 percent of campaign destinations.

Android impressions increased 25 percent ? the largest month- over-month increase and Apple increased and remained the No. 1 device manufacturer with 39 percent share of impressions.

?While we focus SMART on providing insights to brand advertisers about new and existing trends in mobile, we closely monitor device trends on our network as well,? Ms. McKelvey said.

?This month, we added two new Quick Stats - RIM and Android network impressions,? she said. ?Android exploded this month, with a 25 percent increase in impressions.

?Apple and RIM continue to be the OS leaders, but Android is increasingly adding opportunity for advertisers.?