What a PWA can do
- Install to the home screen straight from the browser, no app store required
- Full-screen mode without the address bar
- Work offline: data is stored on the device and synced later
- Push notifications, including on iPhone
- Camera: photos, video, barcode and QR code scanning
- Geolocation
- Updates reach every user at once, with no app review
What it takes to turn a website into a PWA
- HTTPS: without a secure connection, the browser won't let users install the app
- A Web App Manifest: the name, icons, colors and display mode
- A service worker: a script that caches data and responds when there is no network
- Icons in the required sizes, including a separate icon for iOS
A PWA is not a separate product but a layer on top of a website. That means you can also turn an existing web app into a PWA, as long as its interface works well on a phone.
Push notifications on iPhone
For a long time the main argument against PWAs was the lack of notifications on iOS. Since iOS 16.4 (2023), Safari has supported web push for sites added to the home screen.
There is an important condition: until the user installs the app, notifications on iPhone are unavailable, so the interface should show people how to do it. For reliability, important notifications can also be sent to Telegram - that is how we did it in Tandem.
Where a PWA hits its limits
- Background tasks: the browser won't let an app run in the background for long, especially on iOS
- Bluetooth and NFC: Web Bluetooth and Web NFC are not supported in Safari on iPhone
- Deep system integration: widgets, CarPlay, Apple Watch
- Heavy games and 3D that push the device to its limits
- The app store as a sales channel, if that is exactly where customers look for you
How users install a PWA
- Android, Chrome: open the browser menu, then tap “Install app” or “Add to Home Screen”
- iPhone, Safari: tap the Share button, then “Add to Home Screen”
- Computer, Chrome or Edge: click the install icon in the address bar
Many users don't know a website can be installed, so show the hint inside the app itself and at the right moment: for example, after the first successful action rather than right when someone opens it.
Side-by-side comparison
- Development: a PWA has one codebase for phones and computers, while a native app usually needs separate versions for iOS and Android
- Publishing: a PWA is available via a link right away, while a native app goes through App Store and Google Play review
- Updates: a PWA updates for everyone at once, a native app only when the user updates it
- Installation: a PWA installs from the browser in a couple of taps, but users need a hint; people are used to looking for native apps in the store
- Device capabilities: native apps get broader access - background work, Bluetooth, NFC, widgets
Example: Tandem
Tandem is a private app for a couple that we built as a PWA. It has mood check-ins, recurring tasks, a food diary with a barcode scanner that uses the camera, and letters to the future.
The app works offline and sends push and Telegram notifications, and the data in Supabase is protected by row-level security (RLS): each person sees only their own. Publishing a product like this in the App Store would mostly have added review and slower updates.
How to decide
- The app is used on a phone now and then - a menu, bookings, orders, a customer account: start with a PWA
- You need to test an idea quickly and cheaply: a PWA
- A key feature needs background work, Bluetooth, NFC or widgets: a native app
- The app store is your sales channel: a native app
If a PWA does not fit the task, we tell you at the start.
