SingTel said yesterday that it has completed network upgrades along North-East Line from HarbourFront to Punggol.

The telco has also said it has improved mobile signals along parts of Circle Line.

Stronger 3G connections and faster 4G network are available at 12 out of 29 Circle Line stations from HarbourFront to Caldecott.

Previously, 4G surfing was not available in the MRT underground network with users switching to 3G automatically.

However, North-South Line and East-West Line, two of Singapore's oldest train lines, are still undergoing upgrading.

Maintenance sessions along tracks and in MRT stations take a long time as they can only be carried out during the few hours when trains are not operating.

SingTel is also working on boosting the network in some 90 buildings, such as malls and hospitals.

Through crowdsourcing in the past two months, MySingTel smartphone app and SingTel's website have been letting users indicate 3G weak spots.

SingTel is, in fact, the second telco to achieve nationwide 4G coverage in April this year, after M1 in September last year.

So far, M1 and StarHub's 4G networks have been extended to the underground MRT stations at Bishan, Buona Vista, Dhoby Ghaut and Holland Village.

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