What are the potential steps to consider when upgrading from PHP 5.3 to PHP 7.0 on a Linux-Ubuntu system with apache2?

Upgrading from PHP 5.3 to PHP 7.0 on a Linux-Ubuntu system with apache2 involves several steps such as updating the PHP version, installing necessary PHP extensions, and modifying configuration files to ensure compatibility with the new version. It is important to test the website thoroughly after the upgrade to ensure that all functionalities work correctly. ```bash # Update PHP to version 7.0 sudo apt-get update sudo apt-get install php7.0 # Install necessary PHP extensions sudo apt-get install php7.0-mysql php7.0-curl php7.0-json php7.0-cgi # Modify Apache configuration file to enable PHP 7.0 sudo a2dismod php5.3 sudo a2enmod php7.0 sudo service apache2 restart ```