Top ZetaWatch Alternatives for Mac OS X Monitoring
ZetaWatch is a valuable OS X program designed to display ZFS status directly in your menu bar, offering a quick overview similar to how iStat Menus provides other system information. While ZetaWatch serves its niche well, its compatibility can be tied to specific ZFS releases for Mac OS, potentially requiring changes as the libzfs API evolves. For users seeking broader system monitoring, alternative features, or different platform support, exploring a ZetaWatch alternative is a sensible step.
Best ZetaWatch Alternatives
Whether you're looking for comprehensive system monitoring, specific hardware diagnostics, or simply a different approach to keeping an eye on your macOS system, these alternatives offer robust solutions beyond what ZetaWatch provides.

Time Machine
While not a direct ZFS status monitor, Time Machine is the integral automatic backup solution built into Mac OS X. It keeps an up-to-date copy of everything on your Mac, including digital photos and music. As a free and Mac-exclusive tool, it offers features like Automatic Backup, Encrypted backups, File Versioning, and Incremental backup, making it a crucial component for data safety, albeit not a performance monitor like ZetaWatch.

iStat Menus
iStat Menus is a powerful and popular system monitor for Mac and iPhone. It provides comprehensive hardware monitoring, sitting conveniently in your menu bar, similar to ZetaWatch's placement. This commercial tool ($$) offers real-time monitoring, detailed system info, fan speed control, graphs, memory usage, and remote monitoring capabilities, making it a much more extensive system overview than ZetaWatch's ZFS focus.

MenuMeters for El Capitan
MenuMeters for El Capitan is a free and open-source port of the classic MenuMeters for OS X El Capitan 10.11. It provides monitoring for CPU, memory, disk, and network, integrating seamlessly into the macOS menu bar. While not ZFS-specific, it offers a broad range of system information including CPU temperature, network monitoring, and general hardware monitoring, making it a versatile ZetaWatch alternative for general system oversight on Mac.

DriveDx
DriveDx is an advanced drive health diagnostic and monitoring utility for Mac. Unlike ZetaWatch's ZFS status focus, DriveDx ($$) specializes in monitoring a drive's built-in S.M.A.R.T. status, providing detailed insights into your drive's health. It's a powerful commercial alternative for users concerned about the longevity and performance of their storage devices, offering comprehensive hardware monitoring and support for S.M.A.R.T. data.

SSD-Z
SSD-Z is a free utility designed for Windows and available as a PortableApps.com version, making it less suitable as a direct ZetaWatch alternative for Mac users. However, for those with multi-platform needs, it provides detailed information about your SSDs, including controller, processing tech, and NAND type, along with other disk device information and S.M.A.R.T. data support. Its focus is on hardware monitoring for SSDs.

MiniUsage
MiniUsage is a free Mac application that displays various system data like CPU usage, network flow, battery status, and process names in the menubar. It occupies minimal space while providing essential hardware monitoring and network monitoring functionalities. While it doesn't offer ZFS-specific details like ZetaWatch, its compact and free nature makes it a good general-purpose system monitor for Mac users.

Drive Manager
Drive Manager is a free Windows-based tool designed to help users identify drives of the same type by displaying volume labels and vendor information. As a Windows-only application, it is not a direct ZetaWatch alternative for Mac users. Its utility is primarily for drive organization and identification on Windows systems rather than system or ZFS status monitoring.

Stats
Stats is a free and open-source application for macOS that allows you to monitor various aspects of your system, including CPU usage, memory usage, disk utilization, and sensor information. Its comprehensive hardware monitoring capabilities and open-source nature make it a strong ZetaWatch alternative for users seeking a customizable and detailed system overview on their Mac.

Free Disk Space Monitor
Free Disk Space Monitor is a commercial ($) status bar app for macOS that focuses on displaying the amount of free disk space remaining on your hard drive. While it doesn't offer the comprehensive ZFS status of ZetaWatch, it provides a straightforward and useful metric for disk management. It's a simple, Mac-specific tool for users who primarily need to keep an eye on their available storage.
Ultimately, the best ZetaWatch alternative for you will depend on your specific monitoring needs. Whether it's comprehensive system statistics, detailed drive health, or simply free disk space, the options above provide a robust set of tools to keep your macOS running smoothly. Explore each one to find the perfect fit for your workflow and system oversight requirements.