Ahmedabad has a growing metro with two lines crossing the city — useful for the long east-west commute from the airport area to Vastrapur and out to APMC. The flat fare and air-conditioning make it the easiest way to cover distance.
For everything else, auto-rickshaws are the standard. Drivers will quote tourist prices: insist on the meter, or agree a fare in advance — about ₹30 per kilometre is reasonable. Uber and Ola both operate and remove the negotiation. The BRTS (Bus Rapid Transit) is fast on dedicated lanes but the routes take some study.
The old walled city is best on foot — the streets are too narrow for cars, the cycle-rickshaws too rough, and walking is the only way to see the pols properly. Wear comfortable shoes and bring water.