udemy-dl - Download courses from Udemy for personal offline use
Microsoft Office Excel - Microsoft Office Excel is a commercial spreadsheet application.
SwiftBites - Learn how to code in swift with interactive mini lessons
Google Sheets - Synchronizing, online-based word processor, part of Google Drive.
Mimo - Learn how to code on your iPhone📱
ChartBlocks - Import data, design and share a chart in minutes. Or seconds via the API.