A key obstacle that mobile users encounter is clicking a link only to be greeted by the offer to install an app. The relatively slow process of visiting Google Play to download and install an app means that many people simply don't bother -- and this is something that Instant Apps should help with.
The Instant Apps feature was announced last year at Google I/O, and there was much excitement at the prospect of 'streaming' apps on demand. Now Google has started live tests of Instant Apps for Android so you can try out the feature with the likes of BuzzFeed, Wish, Periscope and Viki.
Instant Apps works by breaking down apps into small chunks so they can be downloaded and run on-the-fly -- only those components that are needed have to be downloaded, meaning that with a reasonable connection speed the process should be all but seamless. In many regardless this can be seen as something of a halfway house between traditional app installs and web apps.
As Instant Apps are a feature of Google Play services, the apps are compatible with Android all the way back to Jellybean. For developers eager to convert their existing apps into Instant Apps-compatible versions, Google has published a series of tips that describe how best to approach the process.
At the moment this is a very limited test, but Google plans to roll things out further in the near future:
To develop an instant app, you’ll need to update your existing Android app to take advantage of Instant Apps functionality and then modularize your app so part of it can be downloaded and run on-the-fly. You’ll use the same Android APIs and Android Studio project. Today, you can also take some important steps to be ready for Instant Apps development. The full SDK will be available in the coming months.
Source: http://betanews.com/2017/01/24/android-instant-apps-2/