After a while it stopped doing even that and now it's just blank, even when I plug a cable in, and doesn't respond to any button presses (even the 'hard reboot' and 'factory reset' combinations).
I bought a wireless charger and have had it on there for about 30 min; the charger detects the phone but the phone is still not responding to anything.
Any ideas what else I can do to revive it ---- or what I should do if it's kaput?
Best answer by Goran
At this point you've done pretty much all you can do. Maybe you could try seeing if you plug it into a computer and try powering on if it'll respond, but I'm doubting that it will...youd probably have gotten some kind of response from your attempting to boot it up.
Just take it in to get looked at.