The MVVM (Model-View-ViewModel) architecture is a design pattern that has gained significant traction in the Android development community over the years. Let's delve into its history and some lesser-known facts about it.

History of MVVM in Android:

1. Origins: MVVM was not originally designed for Android. It was introduced by Microsoft in 2005 for their Windows Presentation Foundation (WPF) and Silverlight platforms. The pattern was created to simplify the event-driven programming of user interfaces.

2. Adoption in Android: MVVM started gaining attention in the Android community around 2015-2016. This was a period when Android developers were looking for ways to write more maintainable and testable code. MVVM provided a clear separation of concerns, making it easier to manage and test.

3. Google's Endorsement: The real boost for MVVM in Android came when Google introduced the Android Architecture Components in 2017. LiveData and ViewModel, two of the main components, fit perfectly with the MVVM pattern. Google's endorsement and the introduction of these components made MVVM the go-to architecture for many Android developers.

Lesser-Known Facts About MVVM in Android:

1. Not Exclusive to Android: While MVVM is popular in Android, it's not exclusive to it. The pattern is used in various other platforms, including iOS, WPF, and web applications.

2. Inspired by MVC and MVP: MVVM can be seen as an evolution of the MVC (Model-View-Controller) and MVP (Model-View-Presenter) patterns. It retains the separation of concerns principle but offers a more decoupled approach, especially in the context of data binding.

3. Data Binding: One of the key features that make MVVM stand out is its emphasis on data binding. In Android, the Data Binding Library allows automatic UI updates when the data changes, reducing boilerplate code.

4. Not Always the Best Choice: While MVVM has its strengths, it's not always the best architectural choice for every Android app. Depending on the complexity and requirements of the app, other patterns like MVI (Model-View-Intent) might be more suitable.

5. Misconceptions about MVVM: A common misconception is that MVVM eliminates all code from the View layer. In reality, while MVVM does reduce the amount of code in the View, some logic might still reside there, especially related to animations or UI-specific operations.

6. Testing Benefits: One of the lesser-discussed benefits of MVVM is how it facilitates unit testing. Since the ViewModel doesn't have a direct reference to the View, it can be easily tested without Android-specific dependencies.

7. Learning Curve: While MVVM offers many benefits, it does come with a learning curve, especially for developers new to architectural patterns. Properly implementing MVVM requires a good understanding of LiveData, Data Binding, and other related components.

In conclusion, MVVM has played a significant role in shaping modern Android development practices. Its emphasis on separation of concerns, testability, and maintainability has made it a favorite among many developers. However, like any tool or pattern, it's essential to understand its strengths and weaknesses and apply it judiciously based on the project's requirements.

In this series, we'll try to create components of MVVM architecture from scratch in Android, in an attempt to understand how it all functions under the hood and why we need it. Stay tuned!