This guide shows how to install the Remote Signature Pad computer app on Mac, so your phone works as a signature pad.
Step 1:
Once the Computer App is downloaded, click once to run.

Mac users: the first time you open the app, hold the Control (Ctrl) key and click (or right-click) Remote Signature Pad Computer in your Applications folder, choose Open, then click Open again in the box that appears. You only need to do this once. If you double-click instead, macOS shows “cannot be opened because it is from an unidentified developer”.
When the app shows “Permission Needed”, click Fix Permission. The app restarts and System Preferences opens at Security & Privacy > Privacy, with Remote Signature Pad Computer already in the lists. Click the lock at the bottom left and enter your Mac password. Tick the app under Accessibility, then choose Screen Recording on the left and tick it there too. If macOS offers “Quit & Reopen”, accept it. You do not need to add or drag anything into the lists. Accessibility lets the app move the cursor to draw the signature; Screen Recording lets it recognise your saved signature window by its title. This appears the first time you run the app, and again after you install a newer version.
Step 2:
For the first time, you would be prompted the below dialog box. Please click the Open System Preferences button.

Step 3:
Please choose the Accessibility menu on the left, you should see the Remote Signature Pad Computer icon unchecked. Check the lock to make changes.

Step 4:
Please enter your mac login credentials to allow amendment.

Step 5:
Lock it back to finish the setting.
