We are currently using an app called "BAND" as an information sharing app. There is a web version and a smartphone application, which is useful for group management.
Although it is this application, sdk and API are provided. https://developers.band.us/develop/guide/api
We have no programming knowledge. I am prepared to learn from 1 if necessary. If you have used the BAND app and have tried to make your own, I would like to ask you to teach.
Also, if you are studying on your own because there is no literature on the internet and no one else is doing it, I would be very happy if you could tell me what kind of procedure you should take to study and create.