Process Explorer

Process Explorer shows you information about which handles and DLLs processes have opened or loaded.

Free Windows PortableApps.com

iStat Menus

iStat is a series of system monitor apps. It's available in different versions: iStat Menus, iStat for iOS and iStat Server as a companion application to the iStat...

Commercial $ $ $ Mac iPhone

Atmonitor

Mac OS X System Monitor and Process Explorer Tool atMonitor is the most advanced monitoring tool for Mac OS X that displays system activity in real-time. It is designed...

• Discontinued The official website is no longer available. Last version, 2.7.1, released on August 2012, can be still downloaded from Wayback Machine.

Free Mac

BitBar

The BitBar app lets you put the output from any script or program right in your Mac OS X menu bar. And it's completely free. An impressive number of plugins have...

Free Open Source Mac

XRG

XRG is an open source system monitor for Mac OS X. XRG allows you to monitor CPU activity, memory usage, battery status, machine temperature, network activity, disk I/O...

Free Open Source Mac

TaskExplorer

Explore all the tasks (processes) running on your Mac with TaskExplorer. Quickly see a task's signature status, loaded dylibs, open files, network connection, and...

Free Mac

iPulse

Using its concise and appealing user interface, iPulse graphically displays the inner workings of OS X on your desktop, menu bar or Dock.

Commercial Mac

px

px tells you what processes are running on your system and how they are interconnected.

Free Open Source Mac Linux BSD

PowerTOP

PowerTOP is a Linux tool to diagnose issues with power consumption and power management.

Free Open Source Linux

MagicanLite

Magican Lite is a free system monitor utility. It could help users monitor CPU and memory usage, watch on download and upload speed and detect temperature of CPU and...

• Discontinued The company seems to be abandoned: no news since 2013. Last version, 1.0.0, released in April 2012, can be still downloaded from Apple Appstore.

Free Mac

Monity

Monity is an advanced system monitor that takes place in macOS Today View and oversees component statistics. FEATURES System monitoring • Uptime, Processes, CPU...

Commercial $ $ $ Mac

OS Track

Keeps track of system resources.

• Discontinued Development seems to have halted in 2012.

Free Mac

Tasks Explorer

Tasks Explorer is a freeware opensource computer program providing functionality for collecting extended information about processes running in system in real time. ...

Free Mac