We used React + Next.JS for front-end and serverless AWS lambda services for real-time video processing. React enabled us to make use of open-source editor components and iterate faster. We could open the system for beta users in about 8 weeks from the start.
The video maker platform was loved by the users. Template options with the simple rich editor were the most liked feature. The responsive web app experience was super helpful. No app installs, no learning curve, no cumbersome processes. The ability to save the output videos on dropbox, google drive, or their own amazon S3 service enabled the users to never lose what they had created.