İstanbul-İzmir Otoyolu is a free travel and navigation app developed by Otoyol Yatırım ve İşletme Anonim Şirketi for Android 9.0. This app is an essential tool for travelers who will drive through the Istanbul-Izmir highway. The app provides location-based information and features, including traffic density on Google maps, oxygen stations, and roadworks locations. The app also allows you to call the emergency assistance center or the toll collection call center quickly.

Other features include the ability to filter and toggle details on the route, view the sales and refill points of prepaid HGS labels sold by PTT, locate and search for fuel stations and electric vehicle charging stations along the route, and check your balance for cash HGS tags. The app also provides an option to query unpaid transit situations and displays the details of the selected violation.

It is important to note that the app requires the sharing of location information and notification settings to be turned on to access its features fully. The app is easy to use and provides an excellent solution for travelers who need to navigate the Istanbul-Izmir highway.