Sabiha Gökçen is on the Asian side. The M4 metro runs from the airport through Pendik and Kartal to Kadıköy. From Kadıköy, a ferry crosses to the European shore, and other rail lines continue. Istanbul Airport, on the European side, is a different metro and a different booking. Do not treat the two as one arrival.
Kadıköy, Moda and the Asian suburbs are the natural M4 journeys. Sultanahmet and Taksim are a metro plus a ferry or a long road. The metro is a strong public option in its own hours, with luggage you can carry. A late flight, a family, or a hotel up a steep street is a car.
Book Sabiha Gökçen by name. The fare is for this airport and the stop you chose. Buddy arranges the driver after you pay, and the trip shows the name, the phone and the vehicle before pickup.
Hours, stops and fares on public transport are set by the operator and they change. What is written here is the shape of the network, not a live timetable. Check the operator on the day you travel.
Booking the transfer with Buddy on Move is the reliable way through Sabiha Gökçen International Airport, because the arrangements are finished before you land. You are not comparing a rank of cars at the kerb, and you are not guessing a meter. On this page you set the airport and the other stop, a hotel, a home or an address, then the date, the time and the vehicle. The fare shown is the full price for that ride. Checkout does not add a booking fee, and the amount stays the same after you pay. If you need the return as well, you add it with its own time and you still see one total before any payment.
After you pay, Buddy arranges a driver for that transfer. The meeting place at the airport is the arrivals meeting point. This is not a hunt for a name on a scrap of paper. The driver's name, phone and vehicle appear on the trip before pickup, so you know who you are walking toward. The same booking works in the other direction, from your door back to the airport, which is often the early-morning ride public transport is worst at. Add the flight number when the airport is the pickup. Buddy uses it to coordinate if the arrival time changes, and does not follow the flight on a live status feed. The driver waits up to 60 minutes after the scheduled landing.
The booking itself is short on purpose. People and bags, so the vehicle you choose actually fits. A date and a time. A stop you can point to. There is no second negotiation when the car arrives, because the fare was already the fare. If the plan changes, you can cancel up to 24 hours before pickup for a full refund of the transfer fare. The cancellation page is there if you want the conditions in full. The form only offers pickup times that are far enough ahead to arrange.
Public transport remains a good choice when you are light on luggage, inside the hours the trains or buses run, and close to a station. Buddy is the easy choice when any of those is untrue: a family, a late flight, a resort off the line, or simply an address you would like to reach without planning three connections. You confirm the fare, you pay, and a driver is arranged for that one ride.