
Description: BaconMockup is a free online wireframing and mockup tool. It allows users to easily create website and app mockups by dragging and dropping elements like text boxes, images, and buttons onto a canvas.
Type: Open Source Test Automation Framework
Founded: 2011
Primary Use: Mobile app testing automation
Supported Platforms: iOS, Android, Windows

Description: Holder.js is an open source JavaScript library that generates placeholder images of any size. It can be useful for mocking up website designs before images are available.
Type: Cloud-based Test Automation Platform
Founded: 2015
Primary Use: Web, mobile, and API testing
Supported Platforms: Web, iOS, Android, API