Two of the most popular apps available for Android devices, are on sale for dirt cheap, at least in India. The two apps are, Poweramp and Nova Launcher Prime.
Poweramp needs no introduction, it stands tall amomg music player apps for Android, and its presets and equalizers are no match for a rival, especially the Loud Speaker preset. You can download a trial version of poweramp and try it before you decide to buy the Unlocker for the full version, but at this price, it makes no sense not to get it.
Nova Launcher, likewise, is not something to introduce to the average user. Simply put, it is the best launcheer app out there, if not the finest app ever made for Android. The launcher has a free version with some pretty cool features, but you are definitely going to want to get the Prime version for Unread Badges, and greater customization.
Poweramp Full Version Unlocker and Nova Launcher Prime are on sale for 10 rs in India. Some people have reported on reddit that Poweramp is on sale for $0.99 in the US.