No U.S. Check-in Use Growth Between Oct. 2010 & Mar. 2011?

comScore’s report about location-based check-in service users provides an interesting look at that world. ReadWriteWeb summarized it like this.

ComScore Says Check-In Users Are Young, Employed & Use Android

But, it goes beyond that. Android users are a large percentage of check-in users but does not yet dominate at 36.6%. The combined check-ins by Android, RIM (BlackBerry), and Apple users is huge though: 87.3%. Microsoft Windows Mobile/Phone, Palm webOS (maybe Palm OS?) and Symbian (mostly Nokia) make up the rest of the 12.7%.

Nearly 1 in 5 Smartphone Owners Access Check-In Services Via their Mobile Device

comScore reported that 12.6 million users in the U.S. used a check-in service during the 3 months edning March 2011. This is, they say, 7.1% of the U.S. mobile phone population. This is in line with the Pew Internet study published last November that reported 7% of adults who go online with their mobile phone use a location-based service.

4% of online Americans use location-based services

Does this mean that U.S. check-in service use has been flat for the six month period when the two data sets were gathered?