System Activity Monitor

Activity Monitor 11.5

Monitors activity on the computer to detect viruses and misuse

PRO: Very complete: controls pretty much everything
CON: A client app needs to be installed on each PC you want to control
Vote: 6.3/10 (100 votes) Platform: Windows

HomeGuard Activity Monitor 9.7.1

Monitor every aspect of the home while away

PRO: Keylogger
CON: no free version
Vote: 9.2/10 (329 votes) Platform: Windows

Microsoft Process Monitor 2.95

Track all the activity in your Windows file system and registry in this free download

PRO: Many tools to manage system processes
CON: Not for novice users
Vote: 4.2/10 (8 votes) Platform: Windows

Desktop Activity Recorder 2.00

A security program designed to monitor and record keystrokes and program usage

PRO: Simple to use
CON: Doesn't allow much sound editing
Vote: 6.4/10 (97 votes) Platform: Windows

System Monitor II 19.8

A program for Windows that monitors a variety of system processes and displays device information 

Vote: 5.4/10 (17 votes) Platform: Windows

Simple System Monitor 3.6.24

Simple system monitoring tool

Vote: 4.5/5 (57 votes) Platform: Android

System Monitor Lite 1.5.2

Most complete and beautiful System Monitor!

Vote: 4.5/5 (41 votes) Platform: Android

MKN TaskExplorer 5.0

Monitors activity online and manages tasks that are completed

PRO: Extended information about each process
CON: Basic documentation
Vote: 6.2/10 (23 votes) Platform: Windows

OS Monitor 3.5.0.7

OS Monitor is a tool for monitoring your Android system

Vote: 4.5/5 (69 votes) Platform: Android

System Tuner 3.20.8

A system suite to monitor and backup apps and tweak your system and CPU

Vote: 4.5/5 (73 votes) Platform: Android