I guess this means that all people have to install the Telegram app on their mobile phone. I am looking for a solution where they don't need to install any specific apps on their mobile phone.
I have created new discussion for this: see How to communicate with Node-RED server on the edge using a mobile phone via the internet?
Yes, it is true that people would have to install an app. On the other hand, it takes care of all of the security for you and also takes care of the phone interaction and the camera.
The problem with a web interface is that you have to securely configure your Node-RED server for the Internet and then think about who might have access to the web site you are creating. How do you make sure that party-goers images are safe and only shared to other party attendees without things leaking everywhere.
Don't forget that you are effectively committing everyone at the party to having their images shared - even if they don't take any, others may take photo's of them.
You, as the owner of the server, are also taking on a commitment to both keep the data safe and to respond to the wishes of anyone at the party.
Will you password-protect access to the site? In which case, users have to be given the site name, enter that into their phones and the password which they also have to enter.
Using Telegram could actually be easier for people in that case.
Boa noite, tudo bem? SerĂĄ que vocĂ consegue postar esse fluxo? Obrigado 
