should I learn ethical hacking as I make a backend for an app? how useful would it be?

To put it simply, security is essential part of any software development process. It's something you must learn as much as possible.

@Aitkotw but how do I learn about security without actually learning how to break a bad system?

@teganburns how do I know my mistake if I haven't exploited it?

@Torbuntu probably true, but not what I'm looking for

@g-m-f will do

@calmyourtities if you know how to build a car, you already know everything about it's exploits and weak points. Same thing with security.

@calmyourtities try cybrary.it
And there are lots of books too
Read it and apply it
Learn as much as you can and keep practicing in virtual machine
Try different things
Think why does it work
Why it doesn't
What if I do this way
If you don't have mindset and natural curiosity of how things work behind it no one ever can become a good at finding vunerbility.

@Aitkotw debatable. I'd still have to know practical ways of doing so.

@Thewebdev looks good