If your iPhone randomly started strobing in the middle of the night (during the witching hour, no less), would you think it’s haunted?
Well, this exact situation has been happening to Redditor NotRealUserNameHomie. The Redditor and his wife have caught both of their iPhones doing something pretty strange late at night — and it isn’t clear what’s causing it.
According to the post, both of the couple’s iPhone XS devices have been strobing between 3 and 4:30 a.m. and they have a slew of night vision surveillance camera video catching their handsets doing it (see below).
While it seems like the setup for a new Paranormal Activity movie, there are a few explanations for it. There isn’t a way to conclusively prove what’s causing the strobing (or rule out a haunted house), but the strobing itself is pretty explainable.
What’s Really Going on?
iPhones can be set to have their camera flash strobe when notifications come in Settings > Accessibility > LED Flash for Alerts. But that doesn’t appear to be the case here.
Instead, the strobing looks very similar to infrared (IR) light. Just try pointing a standard TV remote control at a night vision camera and you’ll see similar results.
In other words, the strobing is likely the TrueDepth’s infrared dot projector going off. But why is it strobing periodically late at night? That part is unclear.
While Face ID could be detecting movement every night around that time, the Redditor noted that the feature is disabled on both of their phones. But Face ID actually isn’t the only feature that uses the TrueDepth camera.
Modern iPhones also use the infrared sensors to determine whether or not you’re looking at the screen. It’s called Attention Aware and it’s used to dim the display or lower the volume of notifications if you’re paying attention to your handset.
Like Face ID, this feature could also be detecting movement. But it’s also possible that this is intended and regular behavior.
For example, the iPhones could be periodically resetting every night or doing some other type of background “maintenance” task. If it involves Face ID or Attention Aware “waking up” and scanning for a face, it could result in the strobing.
And because not everyone has a night-vision security camera, that could go unnoticed by most of us. If you have a Face ID-equipped iPhone and an NV camera, you may want to try this out for yourself.