Game itself is kinda fun. My problem is I'm not going to spend money for coins. The coins earned per level is very low compared to the cost of upgrades and engines. It makes you feel like you're going nowhere progressing. I don't mind spending a little, but you (devs) gotta make it enjoyable first for me to want to. Emphasis on want. Why would I just waste money on coins that will be gone instantly? I'm a gamer so a little grind is ok but that's just crazy.
Tracky Train at Google Play market analyse