Pydio is a Secure File Management and Sync solution. It was formerly called AjaXplorer. Pydio stands for 'Put Your Data In Orbit'. It allows users to manage and share their files across devices. It has a customizable web interface and has clients for Desktop and Mobile devices.
ReadRocket Chat and Wekan are useful online collaboration tools. Both tools are open source and can be downloaded and installed for free.
ReadW3C Markup Validator and Validator.nu are two useful tools that can be used to validate HTML code. W3C Markup validator allows validating xhtml, html, xml, mathml and more. Validator.nu allows validating HTML 5 code. The W3C Markup validator is written in Perl, while the Validator.nu is written in Java. Both tools are actively being developed.
ReadRedmine is a web based project management and collaboration platform. It is based on the Ruby programming language and the Ruby on Rails framework. Its user friendly and easy to install and configure.
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