aPlus+ and Moodle are each specialist solutions that have little to no overlap in functionality. aPlus+ co-exists with Moodle at many of our customer sites.
The following quotes the moodle web site:
Moodle is an Open Source Course Management System (CMS), also known as a Learning Management System (LMS) or a Virtual Learning Environment (VLE). It has become very popular among educators around the world as a tool for creating online dynamic web sites for their students.
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Many institutions use it as their platform to conduct fully online courses, while some use it simply to augment face-to-face courses (known as blended learning).
aPlus+ on the other hand is a specialist assessment and results management solution. Whether your courses are taught in person or online, aPlus+ is the perfect solution for managing assessments and results across your organisation.