TL;DR* Here's what the license entails:
1. Anyone can copy, modify and distribute this software.
2. You have to include the license and copyright notice with each and every distribution.
3. You can use this software privately.
4. You can use this software for commercial purposes.
5. If you dare build your business solely from this code, you risk open-sourcing the whole code base.
6. If you modify it, you have to indicate changes made to the code.
7. Any modifications of this code base MUST be distributed with the same license, GPLv3.
8. This software is provided without warranty.
9. The software author or license can not be held liable for any damages inflicted by the software.
More information on about the LICENSE can be found here
@hoang-innomizetech
First of all: I am not a lawyer and therefore cannot make any legally reliable statements.
It is so if you only execute an application "internally" on your server, e.g. through a web application, then you do not have to publish the code. This is because the license was originally developed so that all people who have a program on their computer that is under the GPL should have the right to view the code and edit it so that the program does exactly what YOU want.
So if you enter a website and use this data to pass it on to a mobile app which is not under the GPL and does not use any plugins or libraries that use it and you do not have to use another license that requires to publish the code you don't have to PUBLISH YOUR CODE!