Another of the problems that have mobile games, it is the abuse of microtransactions and fake ads and nothing skippable, but they give a lot of money to the industry (specially in China). In addition to being the most short-lived compared to most PC & console games (Hardly any apps from early iPhones between 2007 & 2008 can be accessed on modern iOS versions). It doesn't make sense to develop an app that works properly for you without updates for 5 or more years, specially by the new rules of Google Play that won't allow any app with more than two years without updates.
The traditional model of paying once and playing is fading away and mobiles are more for developing free-to-play with micropayments or publishing single-player games through subscription platforms in the cloud.