Swingometer is a utility and toy for projecting the results of future United States elections, based on the previous results and the "swing" or change in margin from the previous election to the next.
Swingometer is based on the original web version at UnlikelyVoter.com, but is optimized for iOS use.
Currently Swingometers are available for the 2010 US House elections and an estimate of the 2012 US Presidential election, though based on the current Electoral College apportionment.