Compare software

lieer vs fetchmail: catalog facts
lieer	fetchmail
Free Free and open source under the GPL-3.0 or later.	Free Free, with source code available on GitLab.
macOS, Linux, Command line	macOS, Linux, Command line
Two-way sync between Gmail labels and notmuch tags Keeps a full local maildir copy of the mailbox	Supports both POP3 and IMAP retrieval Actively maintained with a public security errata page
Only works with Gmail accounts Requires notmuch and command-line setup	Only fetches mail; reading and filtering need other tools Past security issues in optional NTLM support
Downloadable app	Downloadable app
Open source	Open source
License: GPL-3.0-or-later	License not stated
Account needed	No account needed
Works offline	Not stated if it works offline
Official website Full listing and sources Checked October 1, 2026	Official website Full listing and sources Checked October 1, 2026

Catalog facts only. Anything “not stated” is unconfirmed. Check full listings for details.