Android might have swept the market with its huge apps in Play store,but Apple's iOS does have a bit of advantage when it comes to Apps. The apps such as Instagram, IFTTT and many others were held by the iOS for long time.
Cider (In a line description) : Enables domestic binaries and foreign binaries to run on the same phone.
Cider is an OS compatibility architecture that can run applications built for different mobile ecosystems, iOS or Android together on the same phone or tablet. Cider doesn't change your OS(Android) settings,it enhances the device with kernel-managed, per-thread personas to mimic the application binary interface of a foreign OS( Here iOS) , enabling it to run unmodified foreign binaries.
This amazing idea has been developed by six Computer Science PhD students from Columbia University.
Operating system developers would definitely know about binary compatibility techniques.This project includes two new mechanisms : compile-time code adaptation and diplomatic functions.
But for those who do not know completely about OS , Compile-time code adaptation enables unmodified existing foreign source code to be reused in the domestic kernel and diplomatic functions leverage per-thread personas, and allow foreign applications to use the domestic libraries to access proprietary software and hardware interfaces.
A small video proof-of-concept for Cider:
Installing this foreign OS abstraction layer the functions of Android apps remain unaffected. Cider is still in their copyright infringement state and this can't be seen very soon in the market up and running. But this proof-of-concept shows the possibility to merge the ruling OSes of the world.