Yes, you can absolutely use Grab to travel from Singapore Changi Airport to your destination. Grab is the primary ride-hailing service in Singapore and is well-integrated into the airport's infrastructure. Upon arrival, after you have collected your luggage and cleared customs, you should use the Grab app to book your ride. Each terminal at Changi (T1, T2, T3, and T4) has designated "Ride-Hailing" or "Private Hire" pick-up points that are separate from the standard taxi queues. These are typically located on the same level as the arrival hall or in the basement levels; look for signs that say "Private Hire Car" or "Ride-Hailing Pick-Up." It is important to wait until you are actually at the pick-up point before booking, as drivers are not allowed to wait at the curbside for long. Be aware that an airport surcharge (currently around S6toS8 depending on the time of day) will be added to your fare, just as it is with standard taxis. The app will provide a fixed fare upfront, which many travelers prefer for budget transparency.