Installing Docker and using containers

A container image is a lightweight, standalone, executable package of a piece of software that includes everything needed to run it: code, runtime, system tools, system libraries, and settings. In this way you don't need to install lots of libraries and software, you can use an existing image and start a container from it.

We will use a container with Ionic and Android SDK that will allow you to develop and test a mobile application. At the end, you will have an APK file that needs to be signed using Google Play Console and after that you can roll it out to millions of people.

In the same Ubuntu 16.04 in the Virtual Box used before, we will install and configure Docker:

1. Install the GPG key in your system:

curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key
    add -

2. Add a Docker repository to APT sources:

sudo add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu
    $(lsb_release -cs) stable"

3. Update the package database...