7-Build a Mobile App

You'll need the skills to write an app first (skills you can learn easily online—we've shown you Android development and iOS development classes ), or at least a great idea and friends with skills (unless you want to hire one from one of the services we've already mentioned) but developing a mobile app is a great way to spend a good, long amount of time doing one thing and then letting the money come later. If your app is good and fills a real need, it'll get picked up by users, tech blogs, and if you're lucky, featured on the app store you publish it to. If it's a free app that's ad-sponsored, you'll rely on those ads for income. If it's a paid app, you'll get a portion of every sale. Again, it may not be enough to live off of (or it might, depending on what you build and how popular it gets!) but a small stream of side income from an app you built is always a good thing. However, building an app isn't a fire-and-forget operation. You'll have to return to it to fix bugs, re-submit updates, test, respond to comments and reviews, repair it when a new phone or mobile OS breaks it, and so on. It takes dedication and passion to be a mobile app developer, and in some cases it doesn't pay terribly well—but it can pay handsomely if you have a great tool that fills a real need (or a specifically fun game). Depending on the amount of time and energy you have to put into some of these, you may be thinking you should just get a second job. Some of these very well may be more like second jobs than side-gigs that you can do in your spare time, but it's all about where your passion lies and what you do with that spare time now. If you already dabble in mobile development and want to learn how to build apps for iOS, Android, or any other mobile platform, going all out and bringing it to life wouldn't be a waste of your time, and you can get paid for it. Similarly, if you dabble in archeology and go dinosaur bone hunting on the weekends, teaching a class on your findings at the local community college is less of a "job" as it is "show and tell." Whatever you choose, make sure you pick something that matches up with the amount of time and energy you have to offer, and maybe even lines up with your passions. You may find that your passion for writing, for example, leads to a lucrative career blogging on one of your favorite productivity sites (see what I did there?)