
Description: A rule of 3 calculator is a simple tool used to solve proportional math problems. It allows you to enter 3 numeric values and calculates the 4th value based on the proportional relationship.
Type: Open Source Test Automation Framework
Founded: 2011
Primary Use: Mobile app testing automation
Supported Platforms: iOS, Android, Windows

Description: Numbat is an open-source alternative to Microsoft Excel focused on data analysis and visualization. It offers powerful spreadsheet functionality along with built-in charting, statistics, and data manipulation tools.
Type: Cloud-based Test Automation Platform
Founded: 2015
Primary Use: Web, mobile, and API testing
Supported Platforms: Web, iOS, Android, API