Why is iphone randomly restarting?

So recently my iphone 7 had been randomly restarting when i'm in apps. The screen turns black, then loading circle appears and its back to normal. I have all the software updated to the most recent ios as well. So what is causing this, is it a ios bug maybe?

Its not really restarting, just a soft reset. Tends to happen from time to time. Usually because of low memory (not to be confused with storage).

  • Why is my phone freezing and restarting if I only got it 3 weeks ago? I got an IPhone XR for my birthday 3 weeks ago, and about 2 weeks ago it started acting up. It would freeze and restart the whole phone and black out at random times. It's been happening a lot more recently, about 2 times a week my phone will act up. I don't know if the phone is just defective or what.
  • Why does my phone keep restarting and then dying? My phone (I have an Iphone 5s) suddenly died and then restarted. It died before it could restart and then started to restart again. The cycle keeps going on and on. I don't have an old battery and worked perfectly until now out of the blue.
  • Why does my iPhone keep restarting? I have an iPhone 6 and it has the newest updates and stuff. Recently it's been restarting 1 to 3 times a day. I'll be using my phone when it just goes to the black screen with the apple symbol on it. I have no idea why it's doing this. Anyone know?
  • Why do people's iPhones keep restarting? Okay so for the past couple weeks my iPhone has just been like restarting when I'm on it. Well it just thought it was mine and then tonight I was on tumblr and there was this post about it and it was like, "reblog if your iPhone has been restating recently" and there was over 55,000 reblogs so that's a lot of iPhones restarting. Why is this happening to everyone?