Transportation in Istanbul
The most difficult thing in your travel is mostly navigation and transportation; especially, if you are going for holiday a a place that you have never seen before. Street you never know, signs you do not understand. If that vacation is going to be Istanbul, it makes it harder with its streets and regions built thousands year ago and some a few years ago. With its 2 continents and lots of hills, it is a big metropolitan city. On the other side, it has 20 milllion population and 3 million cars. Being a foreigner in that city is really difficult.
Your story is going to start when you landed at the airport or port. The most usual option is a cab or taxi. They are mostly yellow and they have fix rate for each km. It looks like easy but there are thousands of driver. They are uneducated and do not speak English. Possibly they do not know the hotel or place you are going. If you tell them the main location, they can take you easily but if you ask him to take you in front of the hotel or point, you may pay a big amount. If they do not know the place, they try to find by asking people and driving around. ( Rarely they use GPS. )That means you are paying for each minute. Unfortunately some drivers will like to use longer roads to get some more money. It may be better to ask approximate rate before you jump.
Another option you can use is buses. They work in fix places and scheduled times. As they arranged for local citizens, you may not find for lots of historical place. Also they do not work after 23:30 to 06:30. There are yellow minibuses you can use at night. They are a bit more expensive according to bus. Both of them takes longer than taxi and subway. In the morning and afternoon, they will be too crowded too. It may be a bad experience in your holiday.
Subway, Metro and Tram systems are the new and modern way of transportation in Istanbul. They are new, air conditioned, safe and fast. They pass each 10 minutes and very usefull in Sultanahmet, Beyazit, Sirkeci, Galata, Taksim, Beyoglu and Sisli towns. You can easily go to Grand Bazaar, Blue Mosque, Saint Sophia, Topkapi Palace, Spice Bazaar, Galata tower, Dolmabahce Palace and Taksim Square. You can use them with tokens or istanbul transportation card that you load money and use. Card is cheaper than token. You can use 1 card for a few person. You can easily pass from Sirkeci on Europe to Asia side by new metro called Marmaray passing under the sea. It is a nice experience. Also Istanbul High Speed Train is a nice choice if you are going out of Istanbul to Ankara, Eskisehir or Konya.
Ferries are also a nice option to travel between Europe and Asia, along the bosphorus with a wonderful view. They work mostly between 2 continents. It will be nice to go Uskudar and Kadikoy by ferry. You can use them same as subway system. Do not forget that they end at 23:00. There are also seabuses going to Yalova and Bursa from Istanbul. There are 4-5 seabuses everyday.
The most comfortable way to travel in Istanbul is Private transfer companies that you can use for airport transfers and daily rental. As the rates are fixed, you will not have a problem about rate. As they are companies, you always find someone to ask, request, or complain. As you book that services in advance, they will know the address or hotel you go. They will be faster and comfortable. You can rent that cars or minivans daily too. So you can travel in Istanbul easily with your driver. You can just relax and watch the city.