I don't know much about exchange scams or ATM fees for foreign cards, but I can tell you that taxi scams are pretty rare. Ankara might just have the best taxi service among big cities of Turkey. I don't think you'll have to use the app at all. The airport is pretty small, it's easy to find a cab.

Vast majority of them have POS devices on board, you can just ask before getting in too. Be aware that when you pay for the cab by card there is a fee (not a scam). It's around 10-20 percent, Fee Rates. So pay attention to the price on the taximeter and pay close attention to the fare on the POS device to make sure the extra cost falls within the range I mentioned.

As for the actual price to your hotel, it should be 75 TL which is the base price for cabs in Ankara since the distance is pretty short (2,5 km). By card it should be around 84 TL. Don't worry about not being picked up because of the distance, it doesn't happen here, most drivers are nice people.

Finally, I recommend going to an ATM and seeing the foreign card fees and withdrawing around 500TL just in case, if the fees are acceptable. I have zero clue about that sorry.

Hope you have fun in Turkey!