Free PHP 7 server app for Android Kitkat

I’m looking for any PHP 7 server app for Android which is free and works on Android KitKat.

I know there is KSWEB, but it needs me to buy everything just to start it. Even Termux is not available on Android KitKat, and I don’t have enough money to buy a new phone or PC.

Is there any free PHP 7 server app that works on Android KitKat?