Upgrading from PHP 7.0 to PHP 7.1 on Ubuntu 16.04

Ubuntu 16.04 PHP PHP 7.0 PHP 7.1

Apparently there is no official PHP 7.1 available for Ubuntu 16.04, but according to this askubuntu.com post there is a reasonably trustworthy PPA: ppa:ondrej/php which allows the installation of PHP 7.1 (and multiple other versions).

sudo add-apt-repository ppa:ondrej/php
sudo add-apt-repository ppa:ondrej/apache2
sudo apt update

After install you can check the currently enabled version and switch to a different version with the following:

update-alternatives --config php
There are 2 choices for the alternative php (providing /usr/bin/php).

  Selection    Path             Priority   Status