
Description: Zalo is a free messaging and calling app developed by VNG Corporation in Vietnam. It allows users to send text messages, make voice and video calls, share photos, videos, stickers and files, and have group chats for free.
Type: Open Source Test Automation Framework
Founded: 2011
Primary Use: Mobile app testing automation
Supported Platforms: iOS, Android, Windows

Description: Signal is a free, open source, encrypted messaging and voice calling app. It offers end-to-end encryption for secure communication. With Signal, users can send encrypted messages, make voice and video calls, and share media with individuals or groups.
Type: Cloud-based Test Automation Platform
Founded: 2015
Primary Use: Web, mobile, and API testing
Supported Platforms: Web, iOS, Android, API