Alternatives to Pop
Compose and send email from the terminal. The listings below can replace it for an important use case. Each note says what changes if you switch.
The original
Pop
Compose and send email from the terminal.
Replacements
Listings that take over the same core job as Pop.
Himalaya
Manage mail accounts through a command-line client.
Himalaya is a command-line client that reads as well as sends mail, supporting several protocols and local mailbox formats, under MIT or Apache-2.0.
aerc
A terminal email client with vim-style keys, an embedded terminal for composing, and first-class support for git email workflows.
aerc is a full terminal mail client with reading and composing, vim-style keys and git patch tools, but has no Windows build.
NeoMutt
A fork of Mutt that gathered decades of scattered patches into one maintained terminal mail client.
NeoMutt is a full terminal mail client that needs a written configuration file first and has no Windows build, under GPL-2.0.
Similar software
Related functionality, not a direct replacement.
Maileroo Mail Tester
A free web tool that grades a test email for authentication, spam score, DNS and blacklists.