Jira - The #1 software development tool used by agile teams. Jira Software is built for every member of your software team to plan, track, and release great software.
Google Voice - Google Voice gives you one number for all your phones, voicemail organized in an email format, free...
Redmine - Flexible project management web application
TextMe - TextMe is a free calls and messaging application at both local and international levels.
Mantis Bug Tracker - Mantis Bug Tracker is a free and open source, web-based bug tracking system.
Talkatone - Android App on. Google Play. Stop paying for cell minutes, texts & landlines; Turn your iPad or iPod touch into a phone; Call/Text even in areas with bad cell coverage; Call/Text when travelling without paying for expensive international minutes.