Firefox Send is described as 'Send is a free encrypted file transfer service that allows users to safely and simply share files from any browser. With Send you can share file sizes up to 1GB quickly. To send files up to 2.5GB, sign up for a free Firefox account' and is a popular large file transfer service in the security & privacy category. There are more than 50 alternatives to Firefox Send for a variety of platforms, including Web-based, Windows, Mac, Android and iPhone apps. The best Firefox Send alternative is OnionShare, which is both free and Open Source. Other great apps like Firefox Send are Send, pCloud, Wormhole and WeTransfer.