Please, stop using phone numbers. There is no reliable way to hold a phone number. The messaging protocols are insecure. If your service uses phone numbers or SMS, that means it's not secure or reliable.
I hate looking at my phone. I hate using my phone. I don't want to have even more reasons to keep my phone charged and in my hand. Phones suck.
Yes, I'm aware the desktop app is made with Electron. So what? I keep it running almost all the time and I've never had any performance issues with it.
Also it won't work on linux phones.
I had assumed that there would be an alternative to access the service post-creation. My gripe is more with the fact that a phone is a requirement at any point.
To put it another way: imagine I had to send a letter to Signal's HQ in order to make an account. Now, obviously I'm not going to be sending and receiving letters constantly to/from Signal, but the mere fact that writing and sending a letter would be a requirement as part of the process would be at the users personal detriment. That's the point I was trying to get at - that it is forcing the user into a specific method which is undesired, arbitrary, and frustratingly unnecessary.
Would it be bound to the mobile device in any way?
Would it require that a canonical list of registered identities be stored server-side?
How would you impose a cost on spam accounts without burdening users?
Just a few considerations.