The case for mobile gaming
From predatory in-app purchases in free-to-play games, which leave players spending more than they realise, to YouTubers incessantly advertising time sinks with stuttery framerates and uninteresting gameplay: poor examples of mobile gaming have been everywhere recently. Nonetheless, mobile gaming should not be treated as a lost cause, nor a no-man's-land of gaming ethics.
The power of casual gaming
The Nintendo Wii sold over 101 million units in its lifetime. The simple, 1-to-1 correlation with the movement of the Wii remote and movement onscreen - as the gamer swings the remote, their character swings the tennis racket in the same way - made it incredibly easy to pick up and play for all age groups. The Wii's focus on accessible gaming, along with the early days of iOS gaming, are great models for modern mobile games: easy to understand and start playing, and full of breezy fun.
Finding depth in simplicity
By virtue of having a touchscreen and (usually) a single button, the simplicity of mobile platforms is often derided by gamers precisely because it is so accessible. Conflating complexity with depth, however, is a misconception. Roguelikes including The Binding of Isaac and FTL: Faster Than Light develop simple concepts to create challenging and absorbing gameplay. Short VR titles like Superhot are wildly popular. Ultimately, if the game is fun, the device on which it is played usually won't matter - except for the fact that, because so many more people have smartphones, almost everyone will be able to experience it without buying a new device.
Seeking gaming in stranger places
Arguably, some of the most popular mobile games on the planet aren't actually 'games' at all. Logging onto your health app and seeing you've hit your step target may not involve the same processes as finishing a level in God of War, but it can certainly elicit a similar feeling of accomplishment. More and more mobile games (such as Pokémon Go) now involve traveling physical distance; others actively encourage collaboration with players to fulfill targets or objectives. This is called gamification. It can effectively motivate users of apps to form positive habits, sometimes creating substantial health benefits or social change through gaming.
As long as game developers keep ethics and player experience in mind while making mobile games, the medium still has a lot of potential for growth and development, especially as indie studios are experiencing a boost in popularity.