Written in the Java programming language, LimeWire is able to run on any computer with Java Virtual Machine installed. Installers are provided for Apple's Mac OS X, Microsoft's Windows, and Linux. Support for Mac OS 9 and other previous versions was dropped with the release of LimeWire 4.0.10. From version 4.8 onwards, LimeWire works as a UPnP Internet Gateway Device controller in that it can automatically set up packet-forwarding rules with UPnP-capable routers.

LimeWire offers the sharing of its library through the Digital Audio Access Protocol (DAAP). As such when LimeWire is running and configured to allow it, any files shared will be detectable and downloaded on the local network by DAAP-enabled devices (e.g., Zune, iTunes).

Beginning with LimeWire 4.13.9, connections can be encrypted with TLS. After LimeWire 4.13.11, TLS is the default connection preference.

Lime Wire LLC, the New York City based developer of LimeWire, distributes two versions of the program; a basic free version, and an enhanced version, LimeWire PRO, sold for a fee of $21.95 with 6 months of updates, or $34.95 with 1 year of updates. The company claims the paid version provides faster downloads and 66% better search results. This is accomplished by facilitating direct connection with up to 10 hosts of an identical searched file at any one time, whereas the free version is limited to a maximum of 8 hosts.

Being free software, LimeWire has spawned forks, including LionShare, an experimental software development project at Penn State University, and Acquisition, a Mac OS X–based gnutella client with a proprietary interface. Researchers at Cornell University developed a reputation management add-in called Credence that allows users to distinguish between "genuine" and "suspect" files before downloading them. An October 12, 2005 report states that some of LimeWire's free and open source software contributors have forked the project and called it FrostWire. The makers of the LimeWire software have now installed a security device that can track most viruses in files.

LimeWire was the first file sharing program to support firewall-to-firewall file transfers, a feature introduced in version 4.2, which was released in November 2004. LimeWire also now includes BitTorrent support, but is limited to 3 Torrent uploads and 3 Torrent downloads, which coexist with ordinary downloads. As of LimeWire 5.0, an instant messenger has been added which uses the XMPP Protocol, an open source communication protocol. Users can now chat and share files with individuals or a group of friends in their buddy list.

From version 5.5.1, LimeWire has added a key activation, which requires the user to enter the unique key before activation the "Pro" version of the software. This has stopped people from illegally downloading the "Pro" versions. However, there are still ways to bypass this security, for example, there are currently cracks on the internet, or people remain using LimeWire Pro 5.5.1 Beta which also includes AVG for LimeWire and is the first version to include AVG. The most recent stable version of LimeWire is 5.5.14.

On February 15, 2010, Lime Wire reversed its previous anti-bundling stance and announced the inclusion of an Ask.com-powered browser toolbar which must be explicitly opted-out to prevent installation. The toolbar sends web and bittorrent searches to Ask.com, and LimeWire searches to an instance of LimeWire on the user's machine.

In LimeWire versions before 5.0, users could accidentally configure the software to allow access to any file on their computer, including documents with personal information. Recent versions of LimeWire do not allow unintentional sharing of documents or applications. In 2005, the US Federal Trade Commission issued a consumer warning regarding the dangers of using file-sharing networks, stating that using such networks can lead to identity theft and lawsuits. On May 5, 2009, a P2P industry spokesman represented Lime Wire and others at a U.S. House of Representatives legislative hearing on H.R. 1319, "The Informed P2P User Act."

One investigation showed that of 123 randomly selected downloaded files, 37 contained malware – about 30%. In mid 2008, a Macintosh trojan exploiting a vulnerability involving Apple Remote Desktop was distributed via LimeWire affecting users of Mac OS X Tiger and Leopard. The ability to distribute such malware and viruses has also been reduced in versions of LimeWire 5.0 and greater, with the program defaulting to not share or search for executable files.