The MATLAB Web App Server is not intended for use on the public internet due to security risks. It was designed for use within a company's intranet. Hence, if you share web app link with your colleagues outside of your network, they will not be able to use it by default. For more information, about the security risks involved, please refer to these pages:
If you are looking share the web app over the local intranet (such that people in your university or company could use it for example), you can get in touch with your Administrator or IT department to configure the Web Apps server to setup the relevant ports.
That being said, you can consider the following alternatives:
1. You can compile the application with the MATLAB Compiler as an executable, and then upload the executable to a location online and then have colleagues download the executable from there.
2. You can host the Web App Server on your company/university's intranet, and then have colleagues join via VPN into the intranet and then open the web app link. This will not allow anyone outside of the organization's intranet to access the web app.
3. You can host the Web App Server on a private cloud server such as AWS or Azure and have your colleagues access the web app from there.
4. You can upload the relevant ".mlapp" and supporting files to a platform like File Exchange. This would not let your colleagues run the application in the browser, but they would still be able to easily download and use your program.
Lastly, you can theoretically setup the web app in such a way that it can be accessible from the open internet. However, MathWorks does not support or recommend this as it open up security loop holes where the machine in which the web app is hosted can be comprised. That being said, our development team is actively working on a solution that will allow to do this workflow safely.
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