LogTailApp - LogTail is a local and remote (SSH) log file viewer and monitoring application for Mac OS X. It is a pure, modern, document-based Cocoa App
AWS CloudTrail - AWS CloudTrail is a web service that records AWS API calls for your account and delivers log files to you.
Hawk - Hawk provides visual user tracking and error reporting with live screen view, deep filtering and robust access control.
Logmatic - Logmatic is a log centralization, analytics & visualization platform to improve software & business performance.
AppSignal - We monitor the software that makes your customers happy.
log4net - log4net is a tool to help the programmer output log statements to a variety of output targets.