Is my phone hacked? Hidden keyboard!!

[BW84]

I purchased a phone from eBay an S7 Edge. I turn the phone on and begin to set the phone up. all the while my old phone was still connected to my Google account and my Wi-Fi. I noticed on the new phone that there was an invisible or faint seen keyboard, so I immediately did a factory reset. However now there's an invisible keyboard on my old phone that was not there before. could someone have hacked my phone before I received it? and if so how can I get rid of it? and is it possible to have a hidden keystroke app or virus even if the phone was at factory reset when I turned it on the first time?

 

[Dngrsone]

This is a used phone. Is it possible that this keyboard is "burned-in" to the display?

 

[Mooncatt]

My guess is the keyboard is burned into the screen.

 

[BW84]

This is a used phone. Is it possible that this keyboard is "burned-in" to the display?

So what abt my previous phone?... I was using it and there was no signs of a burnt keyboard before I logged into the new one.

 

[Mooncatt]

So what abt my previous phone?... I was using it and there was no signs of a burnt keyboard before I logged into the new one.

The previous owner must have used the keyboard a lot more than you. Burn in is based on usage. The longer you have static images like a keyboard on your screen, the quicker burn in will happen. If you mostly watch videos and rarely any static images, the constantly shifting pixels could prevent any burn in at all.