How to Make Your iPhone Flash When a Call is Received
Follow the steps below to make your iPhone Flash its LED multiple times, whenever a Call or Message is received on your phone.
Step 1. From the Home screen of your iPhone, tap on Settings.
Step 2. Next, tap on General.
Step 3. On the next screen, scroll down and tap on Accessibility.
Step 4. On the Accessibility screen, scroll down to a section titled “Hearing” and tap on LED Flash for Alerts option.
Step 5. On the next screen, Enable the LED Flash for Alerts option by moving the toggle to ON position. Also, make sure that Flash on Silent option is Enabled.