Native application refers to the development of a mobile application for a single platform only. The application is built using computer programming languages ​​and tools that are explicit to a single platform. For example, you can develop a native Android application using Java or Kotlin and select Swift and Objective-C for iOS applications.
Native mobile apps don’t run in the browser, unlike websites and web applications. You’ll need to download them from specific app stores like the Apple App Store and Google Play. Once installed, you can easily access any application just by tapping its icon on your device screen.

Benefits :
o Native Apps live on the device and are accessed through icons on the device home screen.
o They can take full advantage of all the device features — they can use the camera, the GPS, the accelerometer, the compass, the list of contacts, and so on. They can also incorporate gestures (either standard operatingsystem gestures or new, and app-defined gestures).
o Native apps can use the device’s notification system and can work offline.
o Publishers can make use of push-notifications, alerting users every time a new piece of content is published or when their attention is required.
o Native Apps maintain UI design of each operating system, thus they offer the best user experience. For example, a Native App can have a left-aligned header in Android and a center-aligned header in iOS.
o Redistribution is easy, as it is found in app store.

Disadvantages :
o High cost for building the app : Native apps developed for one platform will not run on another platform. An App built for Android will not run on iOS. We need to build a different App altogether for iOS. Because of this reason, we need to maintain multiple versions of the App.
o Even though you might publish native Apps, you’ll want to keep the mobile website well maintained, as mobile brings more traffic. So maintenance is higher.

A hybrid app is one that is written with the same technology used for websites and mobile web implementations, and that is hosted or runs inside a native container on a mobile device.

Benefits :
o Developing a Hybrid App is cheaper than developing a Native App. It can be built for cross-platforms, i.e., reduced cost for App development.
o Maintenance is simple, as there are not many versions to be maintained.
o It can take advantage of a few features available in the device.
o It can be found in the App Store, which makes the distribution easy.
o It has a browser embedded within the app only.

Disadvantages :
o Graphics are less accustomed with the operating system as compared to Native Apps.
o Hybrid Apps are slower than Native Apps.

Web apps are not real applications; they are actually websites that open in your smartphone with the help of a web browser. Mobile websites have the broadest audience of all the primary types of applications.

Benefits :
o Easy access.
o Easy Development: Developing responsive design and restructuring the content to be properly displayed on a smaller screen/hardware will make any desktop website mobile friendly.
o Easy update: Just update in one location and all the users automatically have access to the latest version of the site.
o No installation required, as compared to native or hybrid app.

Disadvantages :
o Mobile websites cannot use some of the features. For example, access to the file system and local resources isn’t available in websites.
o Many existing websites don’t support offline capabilities.
o Users won’t have the app’s icon on their home screen as a constant reminder. The website needs to be opened in a web browser only.
o While native and hybrid apps appear on the App Store and Google Play, web apps won’t. So redistribution is not that sensible.

By testing on virtual machines, developers and testers can monitor how the software is performing on a specific device. Compared to real device testing, virtual testing mimics real devices and creates a virtual mobile device on a computer. The two types of programs used for virtual testing devices are emulators and simulators. Even though these terms are used interchangeably, each type comes with different capabilities and limitations. 

What are Emulators? 

Emulation is the process of enabling a computer system (the host) to mimic the hardware and software features of another target device (the guest). Emulators are essentially used as “substitutes”, which replaces the original device for real use. 

• Emulator’s Capabilities: The emulator provides virtual device instances with near-native capabilities and extended controls to adjust the target/mobile device’s physical sensors, battery state, geolocation, and more.
• Emulator’s Limitations: In most cases, the near-native capabilities of an emulator include significant performance overhead due to binary translation. For Android apps and website testing, virtual mobile device emulators can be unreliable since they run slower than real Android devices. Because emulators cannot fully mimic real-world conditions, the testing results won’t be accurate for final releases. 

What are Simulators? 

Simulation is the process of modeling an environment to mimic the behavior and configuration of another target device. Compared to emulation, a simulator is used for “analysis and study”. By using a simulator, you create a virtual environment that mimics the target device from the real world. Ultimately, the simulation process shows you how the device would work in the real environment. However, a simulator doesn’t exactly follow the activity of the real environment.

• Simulator’s Capabilities: An iOS simulator sits on top of your operating system and mimics the iOS by running your app inside it. You can view this simulation in an iPhone or iPad window. Machine-language translation isn’t involved, so the iOS simulator is faster than the Android emulator. 
• Simulator’s Limitations: Unfortunately, the iOS simulator can only be used on a macOS platform. This is because the simulator relies on Apple’s native Cocoa API to handle the GUI, runtime, and more. Compared to Android emulators, simulators cannot mimic battery states or cellular interrupts as well. 

Functional Testing :-
Functional testing is the most basic test for any application to ensure that it is working as per the defined requirements.

Compatibility Testing :-
The purpose of a mobile app compatibility test, is to ensure an app’s key functions behave as expected on a specific device, platform and OS version.

Localization Testing :-
Nowadays, most of the apps are designed for global use and it is very important to care about regional trails like languages, time zones, etc.

Laboratory Testing :-
Laboratory testing, usually carried out by network carriers, is done by simulating the complete wireless network. This test is performed to find out any glitches when a mobile application uses voice and/or data connection to perform some functions.

Performance Testing :-
Mobile performance test covers client application performance, server performance, and network performance.

Stress Testing :-
Stress testing is a must to find exceptions, hangs, and deadlocks that may go unnoticed during functional and user interface testing.

Security Testing :-
Vulnerabilities to hacking, authentication, and authorization policies, data security, session management and other security standards should be verified as a part of mobile app security testing. Applications should encrypt user name and passwords when authenticating the user over a network.
One way to test security related scenarios is to route your mobile’s data through a proxy server like OWASP Zed Attack Proxy and look for vulnerabilities.

Memory Leakage Testing :-
Mobile devices have very limited memory as compared to other computers, and mobile operating systems have a default behavior to terminate applications that are using excessive memory and causing a poor user experience.
Memory testing is exceptionally important for mobile applications to ensure that each application maintains optimized memory usage throughout the user journey. It is recommended that we conduct memory testing on the actual target device, since the system architecture is different from an emulator to an actual device.

Power Consumption Testing :-
There are several types of batteries used in different mobile devices (i.e. nickel cadmium/lithium ion/ Nickel metal hybrid). While we focus on power consumption testing, we are required to measure the state of the battery at each activity level. It will give us a better understanding of power consumption by an individual application.
Power Consumption test can be done manually; also there are some free tools available in the market such as Trepn Profiler, Power Tutor, and Nokia Energy Profiler. These are applications which can display the real-time power consumption on a smartphone or tablet.

Interrupt Testing :-
An application, while functioning, may face several interruptions like incoming calls or network coverage outage and recovery. This can again be distinguished for:
 Incoming and Outgoing SMS and MMS
 Incoming and Outgoing calls
 Incoming Notifications
 Battery Removal
 Cable Insertion and Removal for data transfer

Usability Testing :-
Usability testing evaluates the application based on the following three criteria for the target audience:
 Efficiency: The accuracy and completeness with which specified users can achieve specified goals in a particular environment.
 Effectiveness: The resources expended in relation to the accuracy and completeness of goals achieved.
 Satisfaction: The comfort and acceptability of the work system to its users and other people affected by its use.

Installation Testing :-
Installation testing verifies that the installation process goes smoothly without the user having to face any difficulty.

Uninstallation Testing :-
The basics of uninstallation testing can be summarized in one line as “Uninstallation should sweep out data related to the App in just one go”.

Updates Testing :-
We need to be very much cautious about mobile app updates. People frequently complain about applications not working satisfactorily after an update. So it is very important that under the update testing, we qualify that the App will work as it was working previously.
In a nutshell, it should not break anything. Mobile application updates can take place in two ways – Automatic update and Manual update.

Charles Proxy is a web debugging proxy tool that can be used to monitor and tamper with web traffic. It can be used to debug web applications, inspect HTTP requests and responses, and even simulate slow internet connections.

• Executing test cases with various operating systems
• Testing application’s functionalities on a wide range of handsets
• Screen size fragmentation
• Testing applications on different mobile networks
• Different application types (native, hybrid or web app) require different ways to test
• The choice of the right mobile testing tool for QA team

There are various tools available in the market like google play or app store from where you can install apps like CPU Monitor, Usemon, CPU Stats, CPU-Z etc these are an advanced tool which records historical information about processes running on your device.

Seetest, Perfecto Mobile, BlazeMeter, AppThwack, Manymo, DeviceAnywhere etc.

The number of digits in a mobile phone number decide the maximum mobile phones we can have without dialing the country code.