Quick Guide to Progressive Web Apps One Codebase, Native-App Speed, and Offline Reliability

In today's tech world, it's common to have both a website and a mobile app. Unfortunately, this often means maintaining three separate codebases: one for desktop, one for Android, and one for iOS. But there's a solution for building mobile and desktop apps with the same code. It's called a Progressive Web App (PWA).

So what exactly is a PWA? It's a website that offers an app-like experience, which can be installed like a native app. PWAs provide several advantages: they're fast to implement, can send notifications, load quickly, and even work offline.

And you don't need to publish them in the App Store or Google Play, which reduces your time to market.

Key Takeaways

• PWAs are transforming the way we perceive web apps.

• No app stores needed, no heavy downloads, just “add to home screen” and done.

• For developers and testers, it’s a more straightforward, faster way to deliver real app experiences using web standards.

Let's dive into a practical example. Say your company offers tools for the construction industry, including measurement tools. Some manual tools need a special calculator because the formulas are complex.

You create a website with all these calculations and a great UI. However, users require internet access, and they often have to wait until they have coverage, as they frequently work in remote areas.

In this case, you can transform your calculation subdomain into a PWA. Users can install it on their mobile phones or laptops and use it offline in the browser, or even as a native application.

At Oshyn, we have implemented complex PWAs, integrating them across subdomains. One project implementation involved a subdomain where users performed all their actions, and a separate subdomain where users authenticated with high security standards. We made several customizations, for example, redirecting users to the login domain instead of the public domain when they log out, just like the web version does. This ensures a seamless experience, akin to that of a native application. Since the application always needs an internet connection, we also implemented an offline page within the PWA. As you can see, there are many options for creating a PWA, depending on your business needs.

PWAs are an excellent solution for teams that want to deliver an app-like experience without needing to publish to the App Store or Google Play.

Here are some popular use cases:

• E-commerce: Let users browse and shop even when offline.

• Banking or logistics dashboards: Faster load times and secure caching.

• Company tools: Easily installable and updatable without IT setup.

In short, a PWA offers the best of both worlds: the web and mobile.

If you want to publish your PWA in the App Store or Google Play, you can do so using tools like PWABuilder.

How to Install and Test a PWA

You can test a PWA in three main environments: desktop, Android, and iOS/macOS.

Let's use this demo page.

Test on Desktop

1. Open the PWA link in Chrome, Edge, or Firefox.

2. If the app supports installation, you’ll see a small install icon in the address bar.

3. Click Install → confirm → and now you can open it like a desktop app.

4. You can test offline mode by disconnecting your Wi-Fi; the app should still load.

The Application will appear in the Windows Programs or Launchpad in macOS.

Test on Android

1. Open Chrome and go to the PWA link. pwamp

   https://microsoftedge.github.io/Demos/pwamp/

2. You’ll see a banner or prompt saying “Add to Home Screen.”

3. Tap it → confirm → the PWA installs like a standard app.

4. Try closing Chrome and launching it from your home screen — it should open in a standalone window, not in the browser.

Test on iOS and macOS (Safari)

Since iOS doesn’t show automatic prompts, you do it manually:

1. Open Safari → go to the PWA site.

2. Tap the Share icon (the square with an arrow).

3. Scroll and select 'Add to Home Screen'.

4. Tap Add and return to your home screen — you’ll see the new icon.

5. Open it: it runs like an app, full screen, no Safari bars.

6. Test it offline to confirm if it caches data correctly.

(The images above show each of these steps visually — from “Add to Home Screen” to running the app like a native iOS app.)

Wrapping Up

Ultimately, the power of Progressive Web Apps lies in their simplicity. They represent a massive win for efficiency, allowing teams to deliver an app-like experience from a single codebase. With no heavy downloads and the quick, familiar "Add to Home Screen" process, PWAs tear down the barriers between the web and native applications. If your goal is to provide a fast, reliable, and accessible tool to your users with minimal overhead, the PWA approach is the clear answer. It's time to stop coding for separate platforms and start building once for everyone.

Partner with Oshyn

Ready to implement a powerful PWA? At Oshyn, we specialize in solving complex PWA challenges—including high-security, multi-domain integration and reliable offline functionality, as seen in our work for TCDRS. We help you leverage web standards to build a fast, installable, native-like experience tailored to your business needs. Contact us to transform your vision into a high-performance Progressive Web App efficiently.