Which iPads does this work on?

Anything that can run iPadOS 13.4 or later — the iPad Air 2 and iPad mini 4 from 2014–2015 onward. Older than that, and Safari lacks features the page needs.

No. It is a web page. That is the point — the App Store gave up on these iPads, Safari didn't.

What happens when the wifi drops?

The clock keeps running and the last forecast stays on screen, labelled with when it was read. It catches up when the connection returns.

Nothing. No account, no trial, no tracking.

Skarmly · Guide

Turn an old iPad into a wall clock and weather display

Old iPads stop getting apps long before they stop working. An iPad Air 2 from 2014 still has a bright screen and a charging port, but the App Store has almost nothing left that will install on it — most clock and dashboard apps now require an iOS version it can never run.

Safari has no such problem. That iPad renders modern web pages fine, and a web page needs no install, no account, and no company staying in business. So the trick is to stop looking for an app and put a page on the wall instead.

What you need

An iPad running iPadOS 13.4 or later — that covers everything back to the iPad Air 2 and iPad mini 4, which stop at iPadOS 15 — a charger, and somewhere to stand or hang it. Nothing else.

The setup, step by step

Stop the screen turning off. Settings → Display & Brightness → Auto-Lock → Never. This is the one setting everyone forgets, and without it the display is black within minutes.
Open the display page in Safari. This guide uses Skarmly — pick your town, and the link it gives you is the whole configuration: time, weather, and a background computed from the sun's real position at your coordinates. No sign-up.
Hide the browser. Tap Share → Add to Home Screen, then launch from that icon. The address bar and tabs disappear and the page gets the whole screen.
Turn the brightness down. A wall display lives in the corner of your eye. Set brightness low and turn off True Tone and auto-brightness so it stays put.
Optional: lock it to the page. If the iPad hangs where guests or children tap it, Settings → Accessibility → Guided Access pins one app on screen until a passcode releases it.

Leaving it plugged in

A wall display runs on power, not battery. Modern iPads manage their own charging fine, but an old battery held at 100% and warm ages faster — if the iPad lets you, a smart plug that charges it a few hours a day is kinder. Skarmly's display is deliberately dark, which keeps the panel cool and avoids burning a bright rectangle into a screen that shows the same layout all day; the numerals also drift a few millimetres over time so nothing sits still long enough to ghost.

Questions

Which iPads does this work on?: Anything that can run iPadOS 13.4 or later — the iPad Air 2 and iPad mini 4 from 2014–2015 onward. Older than that, and Safari lacks features the page needs.
Does it need an app?: No. It is a web page. That is the point — the App Store gave up on these iPads, Safari didn't.
What happens when the wifi drops?: The clock keeps running and the last forecast stays on screen, labelled with when it was read. It catches up when the connection returns.
What does it cost?: Nothing. No account, no trial, no tracking.

Skarmly is a free wall display that runs in the browser: the time, the weather, and the sky as it actually is where you are. Set one up in a minute — or see the guide for Android tablets and spare monitors.