Setup steps
Add the Scan Screenshot Shortcut
Tap Add Scan Screenshot Shortcut above and add the shared Shortcut in Apple Shortcuts.
Open Back Tap settings
On your iPhone, open Settings → Accessibility → Touch → Back Tap.
Choose Double Tap or Triple Tap
Pick the gesture you want to use for scanning your latest screenshot.
Select Scan Screenshot under Shortcuts
Scroll to the Shortcuts section and choose Scan Screenshot. Back Tap can now launch SnapAction’s latest-screenshot scan flow.
Why Back Tap needs a Shortcut first
Back Tap does not list SnapAction App Shortcuts directly. iOS only shows user-created shortcuts from the Shortcuts app in the Back Tap picker.
The shared Scan Screenshot Shortcut is a small bridge: it opens SnapAction’s production deep link, and SnapAction handles the latest-screenshot scan flow from there.
Manual fallback
If the shared Shortcut is unavailable, create it manually in Apple Shortcuts:
- Open the Shortcuts app.
- Create a new Shortcut named
Scan Screenshot. - Add a URL action with this value:
com.rescience.snapaction://scan-latest-screenshot- Add an Open URLs action after the URL action.
- Save the Shortcut.
- Assign it in Settings → Accessibility → Touch → Back Tap.
Troubleshooting
Scan Screenshot does not appear in Back Tap
Confirm the Shortcut was added successfully in the Shortcuts app. Back Tap only lists user-created Shortcuts, so the Shortcut must exist before it appears under Settings → Accessibility → Touch → Back Tap.
Back Tap opens SnapAction but does not scan
Make sure you have the current SnapAction app installed. The app must support the production deep link com.rescience.snapaction://scan-latest-screenshot.
I do not see Back Tap on my iPhone
Back Tap availability depends on iPhone model and iOS support. If Back Tap is unavailable, use SnapAction’s in-app scanning entrypoints instead.