Taxis are good transportation to get around Istanbul. They are inexpensive, have meters and most of the time easy to find. Your hotel can call one for you as well. Even at midnight, taxi drivers charge same amount whatever it costs in daytime.
Tram, public transportation works well, inexpensive, but the tram between Zeytinburnu and Kabatas is often quite crowded. There are 2 metro lines. One from the Ataturk Ariport to Aksaray and one from 4 Levent to Taksim. There are 4 tram lines and the most useful one for turists is the one between Zeytinburnu (where you can change for the metro to Ataturk Airport) and Kabatas (near Dolmabahce Palace). It passes many major attractions in the historic center of Old Istanbul like the Blue Mosque, Hagia Sophia and the Topkapi Palace. It passes the bridge over the Golden Horn between the Old and the New Istanbul. From Kabatas there is a funicular connection up to Taksim. From Taksim you can take the nostalgic tram through the major shopping street of Pera (Beyoglu) and then the old funicular (Tunel) down to the bridge over the Golden Horn.You may take either Jeton or Istanbulkart to take the public transportation while in Istanbul.
Jetons for single trips are sold right at the stations and costs 3 liras.
Istanbulkart , Istanbul Metropolitan Municipality Directorate General of IETT Enterprises’ Istanbul kart project is announced as the winner of Mastercard Transport Ticketing Awards, the biggest awards of transport ticketing all around Europe. You can buy Istanbul kart which is valid for all public transportations in Istanbul.
Metrobus, a rapid transit bus route in Istanbul with its 57 stations which follows the city’s ring-road via Beylikduzu, Zincirlikuyu and the Bosphorus Bridge to Sogutlucesme using the dedicated bus lanes for much of the road. It is highly recommended to run away the traffic of Istanbul.
Marmaray, the rail connection between European and Asian Istanbul via a tunnel beneath the Bosphorus, the hearth of the Marmaray line the tunnel that runs beneath the Bosphorus, joining the stations at Yenikapı.