These are the Mobile Phone system layer on which various applications can be developed.
1. Hardware Level:
It is a first level or basic level of the mobile system. All the hardware is integrated in the IC s.
2. Operating system Layer:
It is a layer of Operating system whether it an android or I phone operating system.
3. Libraries/ API (Application Programming Interface)
Libraries or Application Programming Interface can be on one layer and also on different layers.
Above this Operating system, there are various libraries are available which is developed by the OS developer. It is called a Native Library or core library. These Libraries are the set of programs and set of Instructions for the hardware embedded in the mobile device.
Application Programming interface is a software or protocol which used to communicate between hardware and the application layer. APIs act as a bridge between Application layer and the hardware. Each & every hardware has its different APIs.
Applications on application layer works by connecting each & every hardware by connection its APIs.
4. Third Party Library:
Third Party APIs can be developed over the Native library/Native APIs Layer. The Library which doesn’t come as a part of operating system, It is taken from outside or it can be developed; such kind of library is called as third party library.
There are various third party library is available or it is continuously developed. One such kind of library is the Open CV.
Open CV: Open source Computer Vision Library
Open CV is a library of programming functions mainly aimed at real time computer vision. Open CV is used in the different application development.
Open CV focuses on the real time image processing. OpenCV application area includes:
5. Application Layer:
In the application Layer various applications will be developed from the help of the Native Library & 3rd Party Library while connecting with the hardware and OS Layer.
There are also additional libraries with the native libraries. For example, if we want to develop an application in which you record a video by your phone and upload this video in real time on internet.
For that purpose, you have recorded one video but to upload the video in the same format, it is a very long process, for that purpose compression of the video should be done. So, the video can be uploaded easily and also can retrieve easily on internet.
For that purpose an additional library is available on IOS & Android OS. It is not a native library but it is additional library come with native library.
For Another example, if we want to develop one application in which you take a photo by your phone and the application gives you the various images results like concave image etc.
For that purpose, the image should be properly loaded in the application and there should be filters available in the OS library which gives the result which you want. Another example of filter is the font which is a filter of text.