Can video recording and at the same time streaming on a web application be done? Also, how can it be downloaded on the web, considering I have made the web application?
UV4L can record while streaming audio/video in real time with any browser (plug-in free, including mobiles) from a web page that can be customized according to your needs. The recorded audio-video webm can be stored to disk or played back. It works out-of-the-box. The latency with the latest versions is under <150ms in a LAN, the fastest AFAIK. As UV4L is also a framework you can write your web app with the provided REST API. For further informations read through the documentation.