Is there a standard for vibration pattern when a mobile device failed to send an alert that the user needs help?
I've been looking for any standards around haptic feedback of a mobile device when it tries to send out an alert for security but failed. I haven't found any clear answers so hoping I'll get some guidance here. :)
So the app I'm designing is for the security of the user that when they find themselves in a threatening or dangerous situation, they will call for help by pressing a button on the device. But if the device couldn't send the alert for some reason, the user should be made known that the device cant help you, it failed to send the alert.
I have checked a similar answer saying the distress signals are sent in sets of three, but this is not a distress signal, it's a feedback that the distress signal could not be sent. Any recommendations?