The Apple Watch Series 3 smartwatch's much touted function at its launch was its cellular feature. However, just the GPS-only models were available here at launch last September.

The cellular version was finally released here with telco Singtel earlier this month.

This version is practically the same as the GPS-only version in terms of performance, looks and dimensions.

The Series 3 watches have a faster processor - 70 per cent faster than its predecessor - for better performance and which enables Apple's voice assistant Siri to speak instead of just giving text responses.

The cellular version has a red dot on its digital crown to distinguish itself from GPS-only models. It has 16GB of storage compared to 8GB in the GPS-only models.

With its cellular capability, it allows you to be away from your iPhone but still receive notifications, reply iMessages and answer calls. You can also pay for your groceries or post-workout drinks using Apple Pay.

Another nice addition to the cellular Apple Watch is the Explorer watch face, which has a second sub-dial at the six o'clock position and a four-dot cellular strength indicator at the 12 o'clock position. I find this watch face to be the most elegant among the watch face offerings.

In my Series 3 (GPS) review last September, I lamented that the absence of the cellular version would mean the absence of the stainless-steel-case Series 3, high-end Apple Watch Edition and luxury Apple Watch Hermes models here.

All these three models are available now, but only in the cellular version.

Currently, you can use the Apple Watch Series 3 (GPS + Cellular) smartwatch with only a Singtel mobile line. Singtel is offering its NumberShare plan ($6.90 a month, minimum 12 months' subscription), which allows you to share your existing phone number, data and talk-time with the cellular Apple Watch.

The good thing is that you do not need to buy the smartwatch from Singtel. You can buy the Series 3 (GPS + Cellular) from stores here and the NumberShare subscription will be made during the initial setup with your iPhone.

However, take note that if you are a Singtel EasyMobile, Prepaid and Multi-SIM customer, you will not be eligible for a NumberShare subscription.

And if you want to cancel the Multi-SIM plan (like me), you need to head down to the Singtel ComCentre branch to get a brand new SIM card, according to a Singtel operator I spoke with over the phone.

Otherwise, setting up the smartwatch is a breeze, just like with previous Apple Watch models. However, there are additional steps, such as setting up mobile data and entering your NRIC number, before your smartwatch is good to go.

Before you think you can leave your iPhone at home when you go overseas, the Series 3 (GPS + Cellular) smartwatch does not support roaming. So, please take along your iPhone.

But when you are in Singapore, having a cellular connection on your Apple Watch can be liberating. You can go jogging without your iPhone and still be able to stream Apple Music (Spotify and Tidal not supported currently) from the Apple Watch to your Bluetooth headphones.

When making phone calls, no connected headphones are needed. The speakers on the smartwatch do a great job in amplifying the other party's voice during calls. My voice also went across well: my caller thought I was speaking on my iPhone even though I was talking to him via the Apple Watch's built-in microphone.

Battery life varies according to usage. Apple rates its battery life at 18 hours, which include four hours of cellular use. I found that I have around 30 per cent of juice left at the end of a 12-hour day with all e-mail and social media notifications turned on, after having taken two cellular calls of around three minutes each, sent about 40 iMessages and Telegram messages and jogging 5km with it. In other words, you might want to charge the smartwatch every night.

• Verdict: Whether you are using the first-generation or second-generation Apple Watch, you ought to upgrade to the Apple Watch Series 3 (GPS + Cellular) with its cellular connectivity convenience and faster performance. As the owner of two previous generations of Apple Watch, my only question for the cellular Series 3 is - aluminium or stainless steel?