Mazda Demio :: What diagnosis scanner plus app

Hello, my friend got a Demio. The engine lamp lights up. The car has fresh oil and filter, runs great. It was in the workshop. They have dropped horrendous prices including doomsdays. I looked for a Bluetooth adapter for the iPad at amazon. I have no experience with it. The Carly OBD2 scanner sounds promising. The app costs for all vehicles around 70€ plus plugs. At amazon there is also a diagnostic app including plug for 15€ The question is whether I’m just taking a Hunni in my hand and being happy or doing a 15 and similar thing. I’m grateful for tips.