Alpine vs nmail

Alpine: Menu-driven terminal email client descended from Pine, with built-in help, setup screens and native Windows builds.
nmail: Terminal email client for Linux and macOS with an Alpine-like interface and built-in IMAP and SMTP.

Differences

Only Alpine has built-in POP3 and mbox.
On Windows, Alpine runs natively and nmail is not available.
On BSD, Alpine runs natively and nmail is not available.
On Android, Alpine runs through Termux and nmail is not available.
Alpine has mouse support; nmail does not.
Alpine has calendar support; nmail does not.
Alpine has OpenPGP; nmail does not.
Alpine has S/MIME; nmail does not.
Alpine has multiple accounts; nmail does not.
Alpine has threaded views; nmail does not.
Alpine is written in C; nmail in C++.
Configuration: Alpine uses built-in setup screens, stored in .pinerc, and nmail uses ~/.config/nmail/main.conf key=value file.

Side by side

	Alpine	nmail
Interface	Full-screen terminal interface	Full-screen terminal interface
Language	C	C++
License	Apache 2.0	MIT
Latest version	`2.26`	`v5.16.4`
Linux	Native	Native
macOS	Native	Native
Windows	Native	No
BSD	Native	No
Android	Through Termux	No
IMAP	Yes	Yes
POP3	Yes	No
SMTP	Yes	Yes
JMAP	No	No
Maildir	No	No
mbox	Yes	No
notmuch	No	No
OpenPGP	via plugin	No
S/MIME	Yes	No
OAuth2 sign-in	Yes	Yes
Threads	Yes	No
Search	built-in search and message selection; server-side for IMAP	local cache index and server search
HTML mail	built-in HTML-to-text rendering	converted to text, or opened in an external browser
Mouse	Yes	No
Multiple accounts	Yes	No
Offline use	No	local SQLite cache; offline mode and send queue
Calendar	Yes	No
Contacts	built-in address book; LDAP lookup	address book built from messages
Vim-style keys	No	No
Configuration	built-in setup screens, stored in .pinerc	~/.config/nmail/main.conf key=value file

Which to choose

Choose Alpine for

Command list on every screen and built-in help for each option
Official native Windows builds alongside Unix packages
Built-in XOAUTH2 for Gmail, Outlook and Yahoo, and built-in S/MIME

Watch out for

PGP needs external display and sending filters
No Maildir, notmuch or JMAP support
Last stable release is 2.26; newer work is in alpha builds

Install Alpine

Choose nmail for

Built-in IMAP and SMTP with setup wizards for Gmail, iCloud and Outlook
Local cache, address book and outgoing queue can be encrypted
Compose HTML mail using Markdown

Watch out for

One account per running instance
No threaded view and no PGP or S/MIME
Linux and macOS only; no Debian or Fedora package

Install nmail

Questions

What is the difference between Alpine and nmail?

Only Alpine has built-in POP3 and mbox. On Windows, Alpine runs natively and nmail is not available. On BSD, Alpine runs natively and nmail is not available.

Which runs on Windows, Alpine or nmail?

On Windows, Alpine runs natively. On Windows, nmail is not available.