Which one is better?

The end-users generally don’t care whether the application is desktop, web, or mobile, they only want their task to get done efficiently, easily, and fast.

There are continuous improvements in the development of software, whether it is in the user interface (UI), user experience (UX), deployment, or in technologies. It is also observed that the changes are taking place every five years. Shifting from Desktop to Web, Web to mobile APK, Web, and APK to Desktop, Progress Web Page (PWA), Cloud hosting, etc., client-server, multi-tier, XML to JSON, SOAP to REST. Each solution and platform has its own strength and weakness.

Suppose we want to provide flight services to our customers to go from Kathmandu to Pokhara and vice versa. What solution we choose from following two options:

1. Flight solution using Boeing 777 (max speed of 900+ km/hour, max pax 300+ )
2. Flight solution using ATR 42 (max speed of 400+ km/hour, max pax 40+)

We have to select the option based on distance, speed, number of pax, runway facilities, investment, return etc. Similarly, the software solution has to be selected based on requirements and other resources available.

Everything in this world is subject to change. I have a very clear understanding of this context. Nothing is permanent. Market changes, a test of users change requirements changes, the environment changes, working habits changes, looking at the products and services change. In order to go ahead, we must embrace or accept the CHANGE. However, the CHANGE has to be evaluated properly before we adopt it as it could have an impact on many aspects including cost and other resources. Let us get back to our main point Desktop vs Web application and which one is the best?

Over the past decade, there is a constant debate about web apps and desktop apps. Which is better, what are the differences? Which one should be considered for our solutions?  Let us analyze its pros and cons.

What is a Desktop Application?

A standalone application you can install on a computer to carry out a specific task is a desktop application. It can talk to the centralized database server through a VPN. Examples of this type of software are Word, Excel, Powerpoint, Pumori, etc. It utilized the resources of PCs for execution as a result its performance is always better in comparison to web applications.

What is a Web Application?

A web application is software that runs on the web browser and utilizes web technology to carry out different tasks on the web. It requires an internet connection. It uses mostly the server resources and client validation and rendering is done on local PCs. So the utilization of PCs resources is minimum but there are no supplies of PCs with minimum resources nowadays. In this connection, the resources of PCs are wasted. Some of the most common examples of web apps include Google sheet, Google DOC, etc.

What is a Mobile Application?

A mobile application (also called a mobile app) is a type of application (APK similar to EXE files) designed to run on a mobile device, which can be a smartphone or tablet. Examples of mobile apps are Viber, Skype, Facebook etc. Note that mobile apps are similar to desktop apps which have to be downloaded to be used in devices.

Comparision

My Openion:

I hope that you have understood the difference between web apps vs desktop apps.

From the comparison, you must have understood that every application has its own pros and cons, and they can be utilized for specific requirements.

Why mobile apps, web apps like Skype, Viber, Zoom are given as desktop apps for PCs. The reasons are two folds. One is to make it available on all platforms and the other is to enhance performance. I think you may all have noticed the differences.

Desktop Applications can be web-enabled by using CITRIX and similar third-party applications, which will give benefit the both Web and Desktop worlds. The license fee for this implementation will be between USD 60 to 100 per concurrent user.

What is Memory Leak

A memory leak is a kind of resource consumption that occurs when the code does not manage memory allocations while creating the objects. So in order to manage it, the memory used by the object created should be released when not needed. For example, if you call a function or procedure where the object is created and not released then it goes on consuming memories due to multiple calls from the calling programme. A memory leak may also happen when an object is stored in memory but cannot be accessed by the running code.

This could be a serious issue when the system or service is used for 24x7x365 without addressing it. If not handled it will slow down the system by consuming all resources and finally hangs the system.

How to solve it

There are several third party tools available but the simple solution solution is to release or free the used components or objects when not needed while exiting the funtion procedure.

Example:

procedure DoSomething;
var sl : TStringList;
begin
  sl := TStringList.create()
  try
    try
      // code that may raise exception
      sl.Add('suren');
      sl.Add('sujan');
    except
      ShowMessage('Error occured !');
    end;
  finally
    // Free all memory used in this block
    sl.free;
  end;
end;

Note that there are two try blocks are used in above code. They are different and serve two different purposes. First try is used to make all objects free and the second try is used to trap the errors.

The finally block will always be executed, even if there is no exception, while the except block is only executed when there is an exception.

The finally block is even executed when you exit the function early using Exit in a try-finally block.

The except block is meant to handle the exception(s), while the finally block is not. The finally block is meant to contain code that should be executed regardless of an exception, i.e. mainly to protect resources. That is why you should do:

s := b.Create;
try
  // Code that may raise an exception.
finally
  s.Free; // Free resource, even if there was an exception.
          // Exception is NOT handled.
end;

and:

try
  // Code that may raise an exception.
except
  // Handle the kind of exceptions you can handle.
end;

combined :

try
  try
    // code that may raise exception
  except
    // Handle Exception;
  end;
finally
    // Free all memory used in this block
end;

Note the finally block is not limited to memory management. It can be used for other actions like restoring/undo/close opened files, close open connections, shut down hardware that was started etc.

While installing Windows Services, you may get “System error 5 has occurred”  Error or “EOSError Code: 5 Access Denied” Error. This error was due to insufficient permission to run command. The easiest way to run Command Prompt as an administrator is to find the “command prompt” in Search and once you find it, right-click on the “Command Prompt” and then Choose “Run as administrator” to run it with administrative privileges.

Another option is to run in command prompt as below:

C:\net user administrator /active:yes

It is also possible to run netplwiz to solve this error

Windows Service Application

What is Windows Service?

Microsoft Windows service is an application software which runs in the background. Service applications accept requests from client applications, process those requests, and return information to the client applications. As it runs in the background, it does not require user input interaction. These services can be automatically started when the computer boots, can be paused and restarted, and do not show any user interface. The service can have multiple methods to execute at the background level. So it can be used for different background processing like checking system update, processing routines, validations of data etc.

Why do we need it?

Windows services are needed when an application needs to continuously run without user interaction. Services runs until it is stopped or the computer is turned off. When the system needs to respond 24/7/365, then Windows Services Applications are used. When it is running, it is capable of getting requests from clients and return the response.

What are its limitations?

Service Application does not allow to use visual components. Only non-visual components are allowed in service applications. Besides that every processing in the background can be achieved.

When there is a requirement of huge data communication between client and server, DataSnap will be the right choice as it is more flexible and can be deployed as Windows services and Web Services usiing IIS, Apachy and even standalone server.