The qBittorrent project aims to provide an open-source software alternative to µTorrent.
qBittorrent is based on the Qt toolkit and libtorrent-rasterbar library.

Some of the features present in qBittorrent include:

Bandwidth scheduler
Bind all traffic to a specific interface
Control over torrents, trackers and peers (Torrents queueing and prioritizing and Torrent content selection and prioritizing
Cross-platform: Windows, Linux, macOS, FreeBSD, OS/2
DHT, PeX, encrypted connections, LSD, UPnP, NAT-PMP port forwarding support, µTP, magnet links, private torrents
IP filtering: file types eMule dat, or PeerGuardian
Supports IPv6, but cannot use IPv4 and IPv6 at once
Integrated RSS feed reader (with advanced download filters) and downloader
Integrated torrent search engine (Simultaneous search in many Torrent search sites and Category-specific search requests (e.g. Books, Music, Software))
Remote control through Secure Web User Interface
Sequential downloading (Download in order)
Super-seeding option
Torrent creation tool
Torrent queuing, filtering, and prioritizing
Unicode support, available in ≈70 languages[