Taxis, called Karwa taxis, are largely publicly operated by Mowasalat, and can certainly be purchased in the Karwa app or maybe a call centre. You can also find quite a few privately-operate taxis in the region, and Uber operates in Doha. There are plenty of great cars on the market https://social-medialink.com/story968585/the-suv-cars-in-qatar-diaries