Overleaf - The online platform for scientific writing. Overleaf is free: start writing now with one click. No sign-up required. Great on your iPad.
Teachable - Create and sell beautiful online courses with the platform used by the best online entrepreneurs to sell $100m+ to over 4 million students worldwide.
TeXstudio - TeXstudio is an integrated environment for writing LaTeX documents.
Clever - syncing between education applications for K-12 schools
LyX - LyX is a document processor.
Claroline - Claroline is a collaborative eLearning and eWorking platform.