We are working on Child Anti-Abusing App on behalf of the Slovak Republic. Currently we have an Android and iOS app available to the public thats successful in providing help and support. But we need to be more helpful for law enforcement and provide them some kind of unique identifier which could be used in cooperation with mobile network operators to track them down. Right now we are using IP address and software generated identifier. But that's not enough to track them.
Root or Jailbreak is not a option.
Our options:
Legal way to solve this, is request phone number, send them code and process it automatically. This would help a great deal, but we cannot enforce kids entering phone number for various reasons.
Another helpful identifier would be IMEI but that is not accessible on Android nor iOS.
Did we miss any option? Is it possible to get some kind of exception to do it in the background? Ideally without user interaction? Maybe contacting someone in Apple/Google (We are able address official proposal of government)? I would be grateful for any advice.
There is a good way to create a token for each phone by firebase https://firebase.google.com/docs/cloud-messaging/android/client
This feature will not work on Huawei devices that do not have Google services, so you can create a token for Huawei phones as well: I can't get Firebase token from Huawei p40 series device
This method will create a token for the phone, but its downside is that it is subject to change on the device, so you have to create a Firebase database and create an anonymous account on the phone automatically without the need to create a full user account “so that the process remains completely automatic.”