Many of these apps are appealing to people who want to start earning money with little in the way of upfront expenses because they have low entry barriers. The potential fslots jilior making money with smartphone applications is likely to increase, as evidenced by the app economy's ongoing growth. People with different backgrounds and skill sets have continuous opportunity to make money online thanks to this trend. Highest Paying Apps for Passive Income. Swagbucks is one of the best apps for passive income generation.