WeChat is a very unique example of an app. WeChat has emerged from how people in China use the Internet and how it has become integrated into their society. Adoption of cryptocurrency within WeChat would create users but the users of WeChat don't need cryptocurrency because of the massive level of vertical integration that has occurred within the WeChat system. It could be viewed as the complete opposite to crypto because it is so centralized but cryptocurrency solves different types of problems.

Creating a mobile wallet app for crypto is not a major undertaking but the motivation behind that undertaking needs to be defined to make it worthwhile. A wallet is one way for people to transact with their cryptocurrency but the reasons for making those transactions are what matters.