I'm a mobile app developer, author and owner of such apps. My apps are not games but field service tools.
The apps are used to configure and troubleshoot hardware in the field.
Now why did we do this? Short answer. Rather than a custom box we could for less field apps for phones. On top of that the service tech folk tend to keep the phone charged up and keep it from harm. Hammers and tools usually don't get such attention.
Mobile games are not played for the sole purpose of enjoyment alone these days. They have found applications in several other fields as well. We have seen their presence a lot in the field of education. One of the principal application of mobile game development that came to my attention recenlty, is in the field of medical science. For e.g., I have found this game, "Sea Hero Quest" which can help dementia researchers in devising a method for early dementia detection. What do you guys think are the other notable applications of mobile game development?

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