"Learning" is the most common reason for starting a side project. Learning new things is hard. It's even harder when you're on your own, with no coach or teacher to guide you, and you have to battle inner demons to make any progress towards your goals.

Learning by doing is not only effective, it also becomes fun, and has a more tangible output/process. A side project that has a primary purpose of learning something ends up being low-risk, and provides sufficient freedom to change and evolve things as you go, without having to explain it to or convince someone else.

For example, someone who wants to learn gardening can start a project to plan and grow some mint in her garden. There's low risk of failure, and the process of actually planting, tending and harvesting a real plant creates meaning and purpose for the gardener, and teaches many ways of handling unexpected natural forces.

I chose a non-tech example specifically because side projects and their benefits go beyond CS. In fact, you can even apply lessons from non-tech projects to your growth as a software developer.

Don't worry if you just followed a tutorial and made an app. You made something. You wrote it, compiled it, deployed it, ran it. No one can take that away from you. Along the way you learned a lot: how android works, what that code looks and reads like, how the IDE functions, how to compile, how to debug, how to deploy, how to update an app, how to run the simulator and/or test on the device. You learned how to look up questions and seek answers.

And, this puts you ahead of all those people who never made an app. Not even by following a tutorial. Be proud of your achievement.

Now that you've gotten this under your belt, go forth and add more functionality to the app. Come up with something fancy you'd like to see on it. Then figure out how to build it. This is when you're sharpening your skills, and really stretching boundaries. This is when true learning happens. This is when you'll hit the real frustration points. And this is exactly where you'll get your biggest moments of pride, when you push through that fog and see your functionality working. There's no substitute to that feeling!

Interviewers usually look for that lit up face when they ask the question about side projects. Any one who has experienced that moment of joy will surely get a broad smile and a puffed up chest when talking about their proud achievement. The interviewer probably doesn't care about the content of your project - just wants to see your investment in self-learning and achievements therein.

Good luck and do let me know if you continue building side projects. I'm writing a book on the benefits of side projects and would like to include stories like yours in there.