The main function of my app:
- Two users select each other by phone number
- Neither of them is aware of the other at the beginning
- Based on certain activities over time, an event happens for both
Due to Hans-Martin Mosner answer, I'm giving more detail.
When user selects another user he writes data to a server in an entry with a certain id. Unless the other user selects that first user so he can now read that id, he's going to be unable to read that data, and for some time, even if it does, nothing is going to display that it has been able to, until some more things happen.
It's true that, theoretically, once the first read happens I would be able to set a new id for the communication, but due to some of the internal data that the entry with the id already would have, and limitations that the server seems to have, I wouldn't be able to do it with a checking done in the server, although I could do it in the client, but this would open for malicious users, with at least a few of knowledge in hacking, to cheat easily with the app.
Server is highly undesired to be changed at this point of development, something that would go a lot against the app expected behavior due to having it would be needed to change it, so if it's not that big of a problem the issue of the phone number I'll have to stick with it, maybe it's also possible that the limitation I'm mentioning doesn't exist, but after a good investigation I haven't been able to get any evidence that, in my case, it could be done, so I want to know how much inconvenience is to expect the inability to keep on working with a changed phone number and take that information into consideration.
If any of the users changes their phone number during the process, my current solution would require both users to start from the beginning, selecting each other again and starting the whole process over.
The only solution to this problem I can think of would make my app far more susceptible to manipulation by malicious users.
I think that changing a phone number is not that usual (I haven't changed mine in my whole life, and I know few people that have changed it in general) so although it can be annoying for some users, maybe the percentage of affected ones is low enough not to worry much.
I'd like to know with trusted data how much of a problem would that be.