Build the WallCab Shortcut by hand

The nicest part of WallCab is that it does not need to become another app on your phone. Apple already ships the pieces we need: a way to fetch a URL, a way to set a wallpaper, and a way to run those actions on a schedule.

The entire Shortcut

The finished Shortcut contains only two actions:

1. Get Contents of URL points at the address created by the WallCab configurator.
2. Set Wallpaper Photo uses the result as your Lock Screen image.

That is the whole mechanism. There is no account identifier, script, or private deletion token in the Shortcut.

Make your address

On the WallCab homepage, choose one or more learning interests, a built-in visual theme or your own private background, and an iPhone size. The configurator turns those preferences into a readable URL:

/api/wallpaper?categories=science,history,psychology&theme=space&size=max

You can also add an optional note, such as your name. It appears in a PERSONAL NOTE section and adds note= to the address. Leave it blank to remove the section. Because the text is visible in the URL, do not use sensitive information.

Copy the full address. If you ever want to change the edition, replace the relevant word in the Shortcut or return to the configurator and copy a new one.

A custom background adds background= followed by an unguessable ID. That ID lets the renderer use the image, but it cannot delete it. Save the separate private deletion link from the configurator somewhere safe; its secret never belongs in the Shortcut.

Start with the automation

Open Shortcuts, go to Automation, tap +, and create a personal automation with the Time of Day trigger. Choose a morning time, select Daily, and change the run setting to Run Immediately. If you leave Run After Confirmation selected, iOS will ask for approval every day.

Tap Next, choose Create New Shortcut, and search for Get Contents of URL. Add it, paste your complete WallCab address into the URL field, and leave the request method set to GET.

Then search for Set Wallpaper Photo. Make sure it receives Contents of URL, select the Lock Screen you want WallCab to update, and turn Show Preview, Crop to Subject, and Legibility Blur off. WallCab already composes the image for the lock screen, so Apple’s extra crop and blur can damage the layout.

Run the automation once with the play button. This confirms that the selected Lock Screen accepts automated changes and gives iOS the permissions it needs. Then save with the blue checkmark.

The illustrated installation guide shows every important screen and includes fixes for the most common iOS settings.

If your preferred morning time falls before 00:05 UTC, that is fine—the URL still returns the most recently prepared stable edition. The important part is consistency, not a particular clock time.

Why this stays deliberately plain

A plain, inspectable URL is a durable interface. It works in Shortcuts, a browser, curl, and any future automation tool that can download an image. It can be copied, audited, or replaced without asking WallCab to remember who you are.

That is the larger design idea: useful automation should feel like a small tool you own, not a relationship you have to maintain.