How can I secure my Android app’s code and assets from theft after launching?

It might be helpful to have your app validate licenses through your server. Another option is to implement part of your code in the cloud. That way, without a valid license, your app just won't function.

You could encrypt all your code and assets and set it up to decrypt at runtime. I did this for my Cordova app, using custom Java code to handle this. Keep in mind, though, while it adds a layer of difficulty for hackers, determined ones can still get around it. It's about making it sufficiently challenging that it's not worth their time.

In my opinion, don't stress too much over this. Most users won't have the technical skills needed to reverse-engineer your app, and those that do will find ways around any protections you try to put in place. Focus instead on creating your next project. By the time someone is trying to break down this one, you'll already have something new out there!

Legally protecting your app through copyrights, trademarks, and patents is a solid first step. While you can't stop users from doing things on their devices, obfuscation tools can definitely help. However, keep in mind that persistent users might still find a way to reverse-engineer your app. If there's sensitive information that absolutely can't be exposed, consider moving that processing to a secure server instead.

Honestly, there isn't a foolproof solution. Even giant companies like Netflix and Amazon, who invest in DRM protections, still face piracy. At the end of the day, making it clear that someone is stealing from you and having a strong legal approach can serve as a good deterrent.