How to organize video streaming?

Question

Video broadcast

Good afternoon experts.
I was given the task of developing 2 applications:
1. Webinar system. Let's say there's a lesson in the classroom that's being filmed. Any registered user can join and view in real time. In addition, the lesson is recorded in a file, which after the end will be available for viewing.
2. System of paid online consultations (audio/video). That is, the consultant / teacher registers on the site, fills in the schedule - the time at which he is available. Users can request a consultation through the site. During the consultation, a certain amount is withdrawn from the user every minute. Literally, you need a clone of helpouts.google.com .
The questions are this:
1. Maybe someone could suggest ready-made or well-customized open source solutions. Everything I found contained terrible code from many years ago.
2. If there are no solutions from the previous point, then maybe you know developments with good code suitable for learning. Accordingly, it does not have to be open source. After decompilation, I will not steal it, but only study it.
3. PC/smartphone/tablet support is also highly desirable. On how much I understand, in this case Flash on the client is swept aside. Is there a technology that makes it possible to write a single application for all types of devices? For example, html5 with responsive layout.
I have worked with Java / PHP / javaScript / ActionScript3. But for a good solution, learning another language is not a problem.
Thanks in advance.

Answer 1

For the first reason: if you only need video, a video server like Wowza , erlyvideo or something else will be enough for you. If other goodies are needed - can I take a ready-made variant and pay?
On the second occasion: there are a lot of ready-made systems, since they are used in the field of XXX. I won’t tell you here, but you can definitely implement it on the transport, and quite easily.