Istanbul, covering a huge area, is an incredibly crowded and complicated town. Inner city transportation is one of the biggest problems. If you don't know your destination it's very easy to get lost. Don't be confused! Once you learn to deal with the town's “unwritten rules” you'll have great pleasure. Public transportation in istanbul varies greatly. Municipality busses, public busses, inner city and general ships, car ferries, the tunnel, metro and suburban train systems all vary in price and have either tokens or ticket fares to pay. It is essential that you obtain an "akbil", a smart ticket key.
Shuttle bus schedule: http://www.maltepe.edu.tr/en/transportation
When travelling from Kadikoy, you can reach Maltepe University easily by 19H which belongs to iett (public transportation of Istanbul). You should mind the sign (Marmara Egitim Koyune gider) on the bus to be sure it is the right one. For this bus you can use your akbil.
Iett 19H schedule:
http://www.maltepe.edu.tr/en/transportation
Another way (especially if you miss the last bus) is to take a cab. The price should not exceed 20 TL from downtown Maltepe.
http://www.istanbul-ulasim.com.tr/passenger-services/passenger-rights.aspx
