When you arrive
Singapore is very convenient to travel around.
One of the most convenient items to purchase as you arrive in Singapore is a Pre-paid SIM card. You will need your passport number to purchase. There are many desks in arrivals offering many deals. Singtel, Starhub and M1 all offer pre-paid cards there. Click the links to get pricing and locations at Changi Airport.
As you pass by arrivals the taxi ranks are right outside. However, when you're about in Singapore the taxi apps come in handy should you be needing one at any time. Simply search for any of the names in the Play/ App stores to find. Comfort and City cabs are about the most popular. Comfort Cab App for iOS and Android - all other information for travel can be found at the Orchard Road pages here. However, you can get more info here at YourSingapore should you wish to by-pass the shopping centers.