I love a good notification LED - really. When I had my Nexus One back in the day, I absolutely adored my multi-color trackball. I had it decked out with custom colors and pulse speeds using a third party app, and I could tell from across the room if the notification I'd just received was an SMS or a Facebook message just by glancing at the color of that pulsating little trackball.
Notification LEDs, though, seem to rapidly be going the way of the Dodo, or at least just getting crappier. They're smaller, they're harder to see, and there's precious little configurability for the ones we do have. Samsung, though, seems to think the notification LED isn't dead yet, and a rumored implementation provided by Dutch site GalaxyClub.nl on the upcoming Galaxy J2 budget phone actually has me excited about notification LEDs again.
The image at the top should give you an idea of what this new notification LED looks like - the entire border of the area around the rear camera will light up. That is freaking sweet. The biggest problem I have even with fairly bright and bold notification LEDs like those on Samsung's phones is that they're just so small, and totally invisible when your phone is sitting face down. Because they're so small, you generally have to blink them 100% on and off in order for them to be especially noticeable, and that can be extremely annoying if you've got your phone on a bedside table at night (though maybe that just annoys me). A notification LED with much more area could theoretically be softly pulsed while still being easy to see owing to the large illuminated space, or blinked rapidly for maximum visibility. There are certainly a lot of possibilities here. And you'll be able to see your notifications while your phone is face down.
Being Samsung, this new "smart glow" LED doesn't stop at the obvious - it very much tries to be a feature in its own right. Rear camera selfies are actually a pretty great mashup for this thing - you can open the camera app, face the back of the phone toward you, and once the phone thinks your face is centered in the frame, it will be beep and light up the smart glow area blue. That's kind of handy.
Smart glow will also allow you to set notification colors for [probably Samsung-only] app notifications and specific contacts, like some previous Galaxy devices. I don't know about you, but I'm actually pretty interested in this - I've always been a big fan of notification LEDs, and watching them slowly go extinct or become near-useless in recent years has been kind of a drag. Maybe this marks a change in the trend.
The manual from which this information was gleaned has apparently been found on Samsung's support site (warning: large PDF link here), and confirms all of the information in the screenshots - Smart Glow is the real deal. We just don't know exactly how it looks in reality yet.
- Galaxy Club