See for example this page by the developer of the app called "X-Plane", a flight simulator. So far there hasn't been a lot of reporting on this - the Wikipedia page on Uniloc is actually a good summary as of this writing. The basic issue is that if you want to make an Android-licensed app then there are certain procedures Google advises you to follow for verifying that the person running the app does indeed have a valid license for it. Uniloc claims that the procedure is covered by its patents and has spammed out a bunch of lawsuits, including against popular games such as Bejeweled and Minecraft.

As in the Soverain shopping cart situation, there are companies that have decided it's cheaper to license the patent than fight. The patent (6,857,067) itself is a fairly old item and I can't remember what the state of the art was back in when it was filed. However, the patent cites no non-patent prior art, which is a big red flag since it means that almost any trade, industry, professional or academic publication might be fair game for invalidating the patent. At least two of the smaller players who are being sued have vowed to fight back, so perhaps someone will take this one down, too.