An Internet connection today is as basic a need as air, food and water, especially a mobile data connection for Internet on-the-go.

And nowhere is a loss of data connectivity more keenly felt than when you are on vacation, with tonnes of exciting new photos and videos to share on social media.

Data roaming can be prohibitively expensive, and even the smallest bit of overseas data use can result in a huge bill shock upon your return.

However, there are ways to gain Internet access while overseas at affordable rates.

It ultimately boils down to two things: the telco you are on and whether you want to swop your SIM card, or whether you want to carry around an external Wi-Fi device.

Here is a rundown on what you can do to stay connected, and not bust your budget, while you are on vacation.

OVERSEAS PREPAID SIM CARD

The most obvious solution to data connectivity while travelling is to purchase a prepaid SIM card from the country you are travelling to.

They are limited either by data consumption, number of days, or both. For instance, you can purchase a 1GB prepaid SIM that is valid for a week.

The first thing to do is to check if your phone uses a nano or micro SIM card. Most new smartphones use nano SIM, which are smaller than micro SIM cards.

You should be able to purchase SIM cards in most international airports. Some, like London's Heathrow Airport, even sell them at vending machines. Airport SIM cards can be marked up quite a bit though, especially in the United States. If you are venturing into town or a city, check the country's local telcos for better rates on prepaid SIM cards.

You can also purchase them before your flight at Changi Airport. Changi Recommends sells overseas SIM cards that you can pop into your phone while on the plane so that you have data access the moment you land.

This is best for single-country visits. If you are doing a multi-country tour though, you will have to purchase SIM cards in each country you visit.

M1

M1's Data Passport service lets users extend their local data use while overseas for a fee. For instance, customers on the mySIM 30 plan would be able to use their usual 6GB local data bundle overseas if they sign up for Data Passport.

This service has a $2 activation fee and starts from $10 a month per country. It is available in 46 different countries, including popular destinations like Australia, Hong Kong and the US. M1 also extended it to Brazil up till next month to coincide with the 2016 Rio Olympics.

But users will have to make sure they are connected to the correct partner roaming network while overseas. If you connect to a non-partner network, you may get a bill shock upon your return, as those data charges will be pegged accordingly to roaming rates.

Really heavy data users can sign up for unlimited data roaming, which is capped at $15 a day in certain countries.

STARHUB

StarHub postpaid customers have the option of signing up for the telco's DataRoam Daily Unlimited service, which costs $19 a day. This gives them unlimited data roaming on preferred partner networks in 56 countries.

The telco also has a RoamEasy Daily service for those who do not plan to use a lot of data. This costs $10 per 100MB for data roaming on any mobile network in 75 countries.

StarHub offers a prepaid option that is also open to non-StarHub customers. The Happy Roam SIM allows users to consume data in eight destinations - Australia, Hong Kong, Indonesia, Malaysia, Taiwan, Thailand, Britain and the US - without incurring roaming charges.

This starts from $5 for 1GB for three days, and goes up to $20 for a 3.6GB bundle to be used within 30 days.

Frequent travellers can sign up for the RoamEasy Monthly plan. The RoamEasy 400MB costs $40 a month for 400MB of data use on any mobile network in 75 countries. There is also a 1GB option at $100 a month.

SINGTEL

Singtel customers have the most straightforward options for data roaming, if only because they have limited options for it.

Their daily unlimited plans, which range from $19 to $29, depending on the country, cover 110 locations globally.

If you require only small amounts of data, Singtel also offers roaming in 100MB increments, which cost $10. This is capped at a maximum of five increments a day, and data is unlimited after the fifth one.

For short trips in the Asia-Pacific area, travellers can opt for the 30-day ReadyRoam plan, which gives 1GB of data use for $20.

WI-FI ROUTER

If you do not mind carrying around another device, or are travelling in a group, an increasingly popular option is to rent a Wi-Fi router from Changi Airport, which you collect at the start of your trip and return when you come back.

This small device, about the size of a small notebook, connects to the country's LTE or 3G network, and creates a Wi-Fi hot spot that users can hop on to, to connect to the Internet.

These are available for most countries in Europe and Asia, as well as the US. Travellers can get unlimited data, but may experience slower surfing speeds in some countries after they exceed a certain amount of data.

This works best for large groups as the cost can be split between all the travellers. Prices typically range from $12 to $25 a day, depending on the location.

Current promotions until the end of this month include $5 daily fee for Taiwan, $10 daily fee for Hong Kong and $12 for Europe. So, if you are travelling in a group of four to Europe, that works out to only $3 a day for unlimited data.

The downside is that data is available only within the range of the router, which is about 10m. So if the group splits up, some will have to forgo Internet access, which can be troublesome if you rely on apps like WhatsApp or Line to communicate.

The router must also be charged, and battery life varies by location, from four to 15 hours.

It is best to reserve one at least three days in advance by going to the Changi Recommends site at https://www.changirecommends.com/owifi.aspx. You can also do so via phone, e-mail or WhatsApp.

Pickup is done at any of the four Changi Recommends booths at the airport, which are open 24 hours. There are two booths in Terminal 1 and one each in Terminals 2 and 3.

Alternatively, you can purchase your own Wi-Fi router, under the MiFi brand name, for your travels. This requires you to insert your own SIM card - overseas or local - which it will use to create a mobile hot spot.

Huawei makes several versions of these MiFi routers, which retail at between $200 and $400.

This extra step and cost is worth it, perhaps, only for the traveller who flies frequently and always in groups, and to places for which Changi Recommends does not sell Wi-Fi routers.

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