I'm a self-taught Android engineer. What fundamentals should I learn to feel confident enough to apply to jobs?

• Confidence is overrated: It's very hard to be confident when you're starting out, especially if you're a self-aware, hard-working individual. Don't be afraid to just be bold and try things. Failure in software is often cheap.
• In your case, publish your metronome app, get it to a good state, and start applying to jobs ASAP. The worst case is you just get rejected: In that scenario, you can just step back, improve your portfolio, and come back in a month.
• As a self-taught engineer, landing a full-time position off the bat could be difficult. Consider looking for contract work on platforms like Upwork to bridge the gap.
• There's really no roadmaps when it comes to software; a big reason why software is hard is because it's so ambiguous. In your case, the clearest roadmap you can make is to work backwards from the needs of your metronome app and learn those things.
• If I were to make a "roadmap" for an Android engineer starting out, here are the common components:
  • Rendering a list of items
  • Making an API call
  • Parsing a JSON model into a data object
  • Knowing how to navigate from one screen to another (activities or fragments)
  • Standard UI widgets you see in everyday apps like text, images, text input, buttons, etc

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