Before clearing website data: protect your local web-app files

Files and progress that a website keeps inside your browser are deleted together with that website's data, and nothing backs them up unless you make a copy first. That includes every file in a PWA Lock vault and the saved state of a cover app. Clearing Safari's history and website data, deleting a home-screen web app, storage eviction and erasing the phone all count. Here is what is at risk, what removes it, and how to save each vault file first.

What counts as local web-app data?

Most of what you do in a web app lives on the site's servers, and clearing your browser does not touch that. It touches the small set of things the browser holds for the site on this device:

• Files stored by the site. A web app can keep files in its origin private file system, which MDN describes as private to the site and not visible to you like the regular file system. A PWA Lock vault is exactly this: downloads made inside a locked app are written there instead of to the Files app. Where do iPhone web downloads go? explains how that differs from an ordinary download.
• Progress and settings. A cover app keeps its state in the browser: the 2048 board and best score, the calculator history, the timer, the clock's settings, the weather city. None of it is synced anywhere.
• Logins. Cookies remember that you signed in, both to pwalock.com and to the web app itself.
• Drafts and offline copies. Some notes and messaging sites keep unsent or unsynced work on the device; whether yours does is up to the site.

What deletes it?

The home-screen row matters most. WebKit's notes for Safari 17.2 say that when you add a web app to the home screen its cookies are copied over, and after that no other website data is shared with Safari. So a locked app opened in Safari and the same app opened from its icon have two separate vaults, and a file downloaded in one does not appear in the other. Apple's article on clearing Safari data does not mention home-screen web apps, and its guide to removing apps says deleting an app removes its data without singling out web apps. Home-screen web app vs Safari tab covers the rest of that split.

Eviction is the quiet one. WebKit's storage policy says data is removed one site at a time, least recently used first, and that sites are in best-effort mode unless they ask for persistent storage, which PWA Lock does not. Safari's tracking prevention also deletes a site's script-written storage after seven days of Safari use without interaction with that site; WebKit says home-screen web apps keep their own counter and it does not expect their data to be deleted that way. Open and copy a vault you rely on regularly.

Before you clear: the checklist

How do you get files out of a PWA Lock vault?

We make PWA Lock, so this section is specific to its vault. There is no export-everything button and no share sheet: you save files one at a time. The vault's own note says why: files are on this device, in this browser, not encrypted by PWA Lock and not backed up.

1. Open the locked address in Safari or from the home-screen icon, depending on which vault you want. On the lock page, perform the vault passcode, enter the lock password (the vault page calls it the App password) and choose Unlock vault. If you have forgotten the vault passcode, add /__lock/vault to the end of the app's address; the same prompt appears.
2. The vault shows a count at the top, such as 3 files in your vault, and the space they use. Sort by Newest first or Largest first, filter by Images, Videos, PDFs or Other, or search by name so nothing is missed.
3. Each file has three buttons: Rename, Save and Delete. Tapping the file opens a viewer for images, videos and PDFs with Save to device at the top; other types cannot be previewed and show the same suggestion.
4. Save hands the file to the browser as an ordinary download. In Safari, Apple says downloads land in the Downloads folder in the Files app. Apple does not document where a download from a home-screen web app ends up, so try one unimportant file first and find the copy.
5. Repeat for every locked app, since each has its own vault, and for both Safari and the installed app if you have used both.
6. Once the copies are where you expect, Delete empties the vault file by file if you want that before clearing; it asks for confirmation and cannot be undone.

Two boundaries. A saved copy sits in the Files app, outside the lock: anyone who can unlock your phone can open it there. And saving never moves anything: the vault keeps its file, and the original of anything you added with Add files stays in Photos or Files. If you want files that are encrypted and recoverable by design, How to choose a private file app compares what dedicated apps offer and where a vault like this fits.

What does an iPhone backup include?

Apple's guide to backing up an iPhone covers iCloud Backup and backups made on a Mac or a Windows PC. iCloud backups, it says, store information and settings that do not regularly sync to iCloud, such as device settings, home screen layout and app organization. It does not say whether Safari's website data, or the storage of a web app added to the home screen, is included. So do not rely on a backup to bring a vault back; you cannot check what it contains before you erase.

The copies you save are the backup. If your Downloads folder is in iCloud Drive, they sync to your iCloud account as well; if it is on the phone only, move them somewhere you trust.

What happens after you clear?

The next time you open a locked app on that device:

• pwalock.com asks for your account login again wherever the data was cleared, because the 7-day login cookie went with it.
• The lock password, cover passcode and vault passcode still work. They are settings on your account, not on the phone.
• The vault is empty; new downloads land in it. Nothing you saved to the Files app is affected.
• The cover app starts over: a fresh 2048 board, an empty calculator history, a weather cover that has forgotten your city. Cover apps explained lists what each one remembers.
• The web app itself asks you to sign in again.
• If you deleted the home-screen icon, add it again from Safari with Share, then Add to Home Screen; the steps are in the iPhone setup guide.

If you only cleared Safari, open the installed app too and see whether its vault still has files. It may, but Apple does not document it, which is the whole reason to save copies before rather than after.