Well, apart from sending highly targeted updates to citizens, it is also used for:
1. receiving payment request for car tickets that you can pay right away with the credit card you saved in the app
2. receiving pending tax payments for local and national taxes that, again you can pay right away in the app
3. it was used for the national cashback program as a mean to enroll citizens, register the payment cards that could be used to accumulate points, setup banking details to get the prizes, etc...
4. distribute several government incentives (e.g. holiday bonus, bonus for young citizens, etc...)
After I left the project, the team was working on implementing a full digital signature solution that could be used to sign official requests to the public administration and they were also working on supporting legally valid communications from the government (vs just informational).