Mine is also having that same issue right now and it's been about an hour and it's still stuck at 0% I've held down the power button and restarted it anyway to see what would happen and it just brought me back to the same software installation screen
I would reeeeally appreciate help, my sim card has been trimmed and will no longer fit in my back up phone
I am phoneless until this can be resolved!! Also how am i supposed to play pokemon like this. I literally got this phone two weeks ago and it's already stressing me out! I can't find any answers
EDIT:
I FIXED IT.
There are a few other things that others have suggested. Some people say to do a factory reset or hard reset by holding down the volume up button with the power button. However, my volume button was broken at the time so I found another method that works without the potential loss of data.
So what i did was, i took the pin that comes with the phone (the one that you use to take your sim and sd card out) and I stuck it into the small hole on the top of the phone next to the audio jack. I stuck it all the way in, then I held down the power button for about 45 second (or longer) then when i let go, it took me to an android safe restore screen? I actually dont remember what it said, but the little android guy was there. It said to plug the phone's usb in and plug it into the computer and open HIsuite. Which i didn't do.
After it took me to that screen, I took the pin out and held down the power button for a very long time (more than 45 seconds) and when i let go, the phone restarted normally.
This whole ordeal has been stressful, I hope someone is able to read this post and finally solve their issues!
Maybe someone will have a better method or a real answer eventually.
Now i'm just too nervous to restart my phone ever again.