This is an unusual thing to happen because LG G4 is a very powerful phone that is compatible with almost all applications on the Play Store. But, of course, there is the possibility for the application to lack compatibility with this model due to unknown reasons or just because the developer didn't want it on those phones.
Access the link below and try to install it again and if it gives you the same error, contact the developer using the email posted on the official website.
Play Store link: https://play.google.com/store/apps/details?id=com.cmplay.tiles2&hl=en
- Contact email: pianotiles@cmcm.com