A web application is a client–server computer program that runs on a remote server and can be accessed using any browser. They use server-side scripts to manage storage and client-side scripts to display data to users. Web applications are popular because they do not demand complex installations, require very less computing power, can be easily subjected to changes, and solve a great deal of the compatibility issues.

Common examples of web applications include webmail, online banking, online forms, video and photo editing, file conversion, file scanning, online shopping, online auctions, spreadsheets, and more.

Modern Web Applications (MWA) are secure, scalable, flexible, and lightweight web apps that users have come to expect to always available and compatible across all devices and screen sizes. An example of the same are Progressive Web Apps (PWA) these let users download mobile versions of websites on their phones or computers to browse offline.

Static Web Apps: These apps are developed in HTML, CSS, jQuery and CSS, display limited content and are not very flexible. Changes can be made only by the webmaster by downloading the HTML code, making the changes, and hosting it again.
Dynamic Web Apps: These apps are mostly developed in PHP and ASP, and have a database, together with a content management system where administrators can easily add, delete, correct or modify the content. Their content gets updated with each user interaction, and allows an abundance of features to be implemented.

The cost of building a website/web application depends on a number of factors such as:
Functionality: If the app demands complex third-party integrations, multiple APIs, databases, dynamic content, hosting, mobile compatibility and more, it escalates the costs.
UI/UX design: If you desire to go for custom UI/UX designs for your apps than the ready-made design templates, you will surely have to pay more.
Uniqueness of the project: If your app demands specialized knowledge and skill sets from highly-experienced and qualified developers, your app development costs may scale up.

The time taken to build a web application can vary from hours to months depending on the scope of the project, user flows, and designs. The development entails various steps, starting from getting a clear understanding of the requirements to deployment and scaling, and the time taken for each step can vary significantly based on the complexity of the app.

Yes, we provide technical support and service to the websites we have developed during the time we administer them. We can also further develop your website if you need to implement new features or integrate third-party services that weren't there before. However, most of this comes with a cost on the client's part.