Basic features:
- Portable - supports running from USB keys or other removable media
- 64 bit audio engine
- Excellent low-latency performance
- Multiprocessor capable
- Direct multi-track recording to many formats including WAV/BWF/W64, AIFF, WavPack, FLAC, OGG, and MIDI.
- Extremely flexible routing
- Fast, tool-less editing
- Supports a wide range of hardware (nearly any audio interface, outboard hardware, many control surfaces)
- Support for VST, VSTi, DX, DXi effects
- ReaPlugs: high quality 64 bit effect suite
- Tightly coded - installer is just over 2MB

Editing features:
- Tool-less mouse interface -- spend less time clicking
- Drag and drop files to instantly import them into a project
- Support for mixing any combination of file type/samplerate/bit depth on each track
- Easily split, move, and resize items
- Each item has easily manipulated fades and volume
- Tab to transient support
- Configurable and editable automatic crossfading of overlapping items
- Per-item pitch shift and time stretch
- Arbitrary item grouping
- Markers and envelopes can be moved in logical sync with editing operations
- Ripple editing - moving/deletion of items can optionally affect later items
- Multiple tempos and time signatures per project
- Ability to define and edit project via regions
- Automation envelopes