Pre-built libraries for web and mobile applications
I personally suggest for building libraries/SDK that can be customized and produced as varieties.
In other words, it can be compared to a custom built directory script which helps the companies to build all type of listing and deal websites, similarly the next era in software development will be a plug and play type of development.
All software companies can build their code bases or a product that can be customized and produced as varieties to the customer needs.
Lets thread here...