Personally, I avoid any game or application that uses in app payments now, after being burned by developers. The most expensive Android game I have purchased had a single IAP to convert from a one level demo to the full game which was acceptable. When the same game was released with a "micro" IAP model, it was clear quickly that the dev had ruined the game and it would cost a lot more to complete the game. The best part was the payments were mostly for consumables that didn't carry across when starting a new game. They even removed the original game from the store... Their excuse was the usual pathetic nonsense claims of piracy with the old model which always ignores the fact that their new model harms the honest customer far more than any pirate.
Trying a limited demo or ad supported version first and then purchasing a full version or unlocker is my preferred option. Combating intrusive Adware and Spyware from the truly evil developers means that I simply start out not trusting an app or developer at all. There are a small number of developers that have my complete trust and support. The end result is that I now only install new apps very rarely, with a firewall and other security software in place. While that saves plenty of money, it does limit access to the latest games and apps.
Scientists will study your brain to learn more about your distant cousin, Man.