To reserve a 100% app car, you must install the cambioApp. As long as you have not downloaded the cambioApp, you will never be assigned a 100% app car.
We do recommend that you download and use the cambioApp, because more and more 100% app cars will be added. This way you will continue to have access to the entire cambio car offer and that will give you a better chance of finding a car close to you.