FL Studio 9.1 (various pricing, feature-limited free demo) is the latest version of the long-time sequencer and recording app formerly known as Fruity Loops. Despite a slightly non-standard user interface, FL Studio is one of the easier digital audio workstations to use--if you come from a step/pattern-based recording background.
If you're used to Ableton Live, you'll adapt to FL Studio in a heartbeat. However, users of track-based programs such as Cubase, Sonar, or Pro Tools will have a steeper learning curve. You record audio into the playlist for use as parts, or the Edison audio editor insert (added to a track like and effect) to create ad hoc audio tracks. Once you're used to it, there's a certain elegance to this marrying of step- and track-based approach to music creation.
At first glance, you might not notice much new in FL Studio 9.1, but there are literally hundreds of refinements and improvements. Most address bugs and user suggestions to enhance usability, but there are some new features such as the Drumpad instrument, Fruity Convolver reverb, Harmless additive synthesis instrument, Stereo Shaper, and Vocodex vocoding plugin. There's also welcome support for VST3 instruments and plugins as well as multi-core CPU support.
FL Studio is available in four flavors: the $49 Express Edition, $99 Fruity Edition, $199 Producer Edition, and the $299 Signature Bundle. There are some significant differences, and too many to get into here, but you'll find them listed in a document that appears when you close the demo or at vendor Image Line Software's Web site.
All in all, FL Studio is a worthy program that will suit many user's work styles--especially those into electronic or dance music. 9.1 is a nice upgrade, and as always, is free to owners of any version of the program. You buy this program only once, a policy we'd like to see more often in an industry full of companies more concerned with maintaining revenue stream than getting it right the first time.
Note: The demo will let you save a song, but not reopen it.