Short answers toreal PWA questions

Direct, sourced answers — the kind you can share in a Slack thread.

What is a PWA?

A PWA (Progressive Web App) is a regular website that meets three technical criteria — HTTPS, a Web App Manifest and a service worker — so browsers let visitors install it on their home screen. Once installed, it launches like a native app, works offline and can send push notifications.

Can a PWA send push notifications on iOS?

Yes. Since iOS 16.4 (March 2023), a PWA can send Web Push notifications on iPhone and iPad — but only after the user installs it to the home screen. Push in a regular Safari tab is not supported, and the user must explicitly grant notification permission from inside the installed PWA.

Do PWAs work offline?

PWAs can work offline, but only for content their service worker has explicitly cached. Registering a service worker does not automatically make a site offline-capable — you decide what to cache (app shell, API responses, images) and what strategy to use (cache-first, network-first, stale-while-revalidate).

PWA vs native app: what does each cost?

Building a PWA typically costs 30-50% of an equivalent native iOS + Android app because you ship one codebase to three platforms (iOS, Android, desktop). Maintenance is roughly one-fifth: no app-store review, no separate release trains, no platform-version fragmentation.

How do you uninstall a PWA?

On iPhone and Android, uninstall a PWA by long-pressing its home-screen icon and choosing "Delete" or "Uninstall". On Windows and macOS, open the installed PWA, click the three-dot menu in the title bar and choose "Uninstall". The site itself is not affected — only the installed shortcut and its service worker cache.

Are PWAs in the App Store?

PWAs are not in the App Store or Play Store by default — they install directly from the browser. If you want store presence, PWABuilder (from Microsoft) packages a PWA into a Trusted Web Activity for Google Play, an MSIX for Microsoft Store, and a WKWebView wrapper you can submit to Apple.

Why is my PWA install prompt not showing?

Chrome shows the install prompt only when the site passes strict installability criteria: HTTPS, a valid manifest with name, icons and start_url, a registered service worker with a fetch handler, and the user has not previously dismissed the prompt. Any one of these missing is enough to block the prompt entirely.

What are the storage limits for a PWA?

A PWA typically gets 60% of the device disk space on Chrome and Edge (up to hundreds of GB), 20% of total quota on Firefox, and around 1 GB on Safari. Cache Storage, IndexedDB and OPFS share the same quota. Browsers evict least-recently-used origins under pressure unless the site requests persistent storage.

Can a PWA access the camera?

Yes. A PWA can access the camera, microphone, geolocation and file system through the same Web APIs a regular website uses (getUserMedia, showOpenFilePicker, Geolocation). Every capability requires explicit user permission and works cross-platform, though a few APIs (Bluetooth, USB, NFC) are still Chromium-only.

Does a PWA help or hurt SEO?

A PWA does not directly change your Google ranking. Googlebot indexes your HTML the same whether or not you have a service worker. The indirect effect is Core Web Vitals: repeat visits from installed users have near-zero TTFB and better INP, which improves your CWV score and, over time, ranking.

Do PWAs work on iPhone?

Yes. Since iOS 16.4 (March 2023), iPhone and iPad support the full PWA feature set: install to home screen from Safari, standalone launch, offline via service worker, and Web Push notifications. The install step is manual — Safari does not show a browser prompt; users must tap Share → Add to Home Screen.

What are the requirements for the Chrome install prompt?

Chrome fires beforeinstallprompt when the site is served over HTTPS, links a valid manifest with name, start_url and 192px + 512px icons, registers a service worker with a fetch handler, and passes a user-engagement heuristic (typically one interaction and ~30 seconds of use). Any failing criterion silently blocks the prompt.

Can PWAs accept payments?

Yes. A PWA can accept payments through any standard web checkout — Stripe, PayPal, Adyen — and can also use the native Payment Request API to surface Apple Pay on iOS 16.4+ and Google Pay on Android. There is no App Store 30% cut because payments run through the web, not through a native store SDK.

Do PWAs support background sync?

Partially. Chromium browsers (Chrome, Edge, Android WebView, Samsung Internet) support the Background Sync API for retrying failed requests, and Periodic Background Sync for scheduled updates. iOS Safari and Firefox do not support either. Fall back to Push notifications for cross-platform re-engagement.

PWA vs hybrid app — what is the difference?

A PWA is a website users install from the browser — no store, no shell, no native code. A hybrid app (Ionic + Capacitor, Cordova, older React Native WebView apps) wraps the same web code in a native binary submitted to the App Store and Play Store. PWAs are cheaper and faster to ship. Hybrid apps unlock store distribution and deeper hardware APIs.

Do PWAs improve conversion rate?

Yes, when users actually install. Published case studies (Alibaba, Twitter Lite, Pinterest, Uber, BookMyShow) show 30-100% conversion lift after PWA adoption — driven by faster loads, offline support and home-screen install. The effect is largely from install: once your icon sits on the home screen, return sessions jump.

Can PWAs read and write files?

Yes on Chromium browsers (Chrome, Edge, Opera). The File System Access API lets a PWA open, read, edit and save files with the user’s permission — Figma, VS Code Web and Excalidraw use it in production. iOS Safari and Firefox fall back to the standard `<input type="file">` and downloads.

Can PWAs use Bluetooth?

Partially. The Web Bluetooth API works on Chrome, Edge, Opera (desktop and Android) and Samsung Internet — enough to connect to BLE peripherals like heart-rate monitors, printers and IoT devices. iOS Safari and Firefox do not support it, and Apple has stated no intent to ship it.