We refer to Mr Lim Choo Beng's letter (Telco's seniors' offer disappoints, Sept 11).
We contacted Mr Lim and understand that he was not able to make phone calls with a particular smartphone model using the TPG SIM card.
This was because he was using the TPG SIM card on an older smartphone that does not support Voice over Long Term Evolution (VoLTE) technology. VoLTE refers to voice calls taking place on the 4G network rather than the older 2G or 3G network. VoLTE offers better voice quality.
There were no issues with his TPG account or SIM card.
The TPG mobile network is licensed for the roll-out of 4G. This means that traditional voice calls can be made only through mobile phones that support VoLTE technology.
While most newer 4G mobile phones in Singapore support VoLTE, some handsets do not have updated VoLTE settings as mandatory certification on mobile networks is not necessary in Singapore.
TPG has created an easy-to-use 4G voice app called TPG 4G Voice to support users who are using non-VoLTE compatible devices.
Similar to popular messaging platforms like WhatsApp, users can make and receive calls through the app so long as there is data connection.
For making emergency calls such as to 911 and 995, TPG users with non-VoLTE phones also need to use the TPG 4G Voice app. The app can be downloaded from the Google Play Store and Apple's App Store, and installed like any other app.
Having to use the app for regular phone calls can be inconvenient and confusing for less tech-savvy seniors.
The other telcos here do not face this problem because voice calls are generally routed through their older 3G networks when necessary. TPG does not have this older 3G network, placing us at a disadvantage and making it inconvenient for our users to make and receive calls.
We urge the authorities to look into this matter and mandate that 4G mobile phones in Singapore be VoLTE certified on all mobile networks to level the playing field, and to remove the confusion and inconvenience for consumers here.
This is also to allow the public, especially seniors who may be less digitally inclined, to call emergency numbers with ease.