Letters were sent via email from the FTC to the developers of a dozen apps available from the Google Play Store that are believed to contain Silverpush. You can read a copy of that letter by clicking on the sourcelink. The letter says that Silverpush could run silently in the background and "could generate a detailed log of the television content viewed while a user’s mobile phone was turned on."
The use of Silverpush in Android apps could be illegal, but the software is reportedly not in use in the U.S. Even so, the letter from the FTC suggests that developers of those dozen apps tell consumers that their apps will start to collect television viewing information once Silverpush is used in the states. Developers of apps that use Silverpush could be considered responsible if users aren't informed about the collection of data and who is receiving it.
source: FTCLetter, FTC via SlashGear