The following services are supported for Transatel’s MVNOs and subscribers:
– VoLTE Roaming: Make calls on 4G/LTE on applicable partner networks
– SMSoIP Roaming: Send SMS via the 4G/LTE network on applicable partner networks

VoWiFi/SMSoWiFi is not supported in roaming

The current list of partner networks can be found here.

The technology is new – this list will grow as IMS roaming services are opened up with partner networks.

The handset must be attached to one of these networks for the services to work. There are more than one network in every country, and not all networks of every country are enabled (for now). If a subscriber is having difficulty making communications in a country, it may be advisable to manually select one of the above networks via the handset.

All services and charges will continue to function as usual. There are no additional surcharges for these services.

The availability of these services remain the same criteria as national IMS services
– compatible handset
– IMS (VoLTE/4G Calling) activated on the handset
– IMS provisioned
– LTE coverage

Incoming calls identified as 100% spam will always be blocked by HiYa, whether in national or roaming.
With regards to the nuisance call display feature, indeed, Hiya will be available with VoLTE roaming – provided that the host’s network is compatible with the necessary Hiya parameters to support call identification services (some networks may strip out the required tags from the call signalling).