Now that limit has been expanded to a generous 4GB! Android applications will now be able to include expansion files along with their Android apk apps that contain the extra data.
While the app itself will still be limited to 50MB, it will be able to have two additional expansion files, up to 2GB each, which can be included in the app download. This saves app developers the hassle of having to host the data themselves.
Mobile applications are getting increasingly complex, and 50MB simply does not cut it any more. The limited size, capacity, and performance of mobile devices might make it seem like 4GB is too much; however there are many instances where such sizes can be required. Media rich applications, such as games will easily be able to make use of this extra capacity.
Newer devices will support this new option automatically, and will download the expansion files automatically. For older devices Google has created a new library that allows the app to download these files itself.