Commercial use requires 'releases' - editorial use doesn't. Stock photos can be sold for commercial (eg, marketing) or editorial (ie, journalistic) use. You'll have more opportunities to make cash if your photos are available for both, but photos containing people or property (including branding and logos) need signed releases to be sold commercially.
Because smartphones are everywhere, the demand for new and creative apps is increasing in popularity more than ever before. Between Google’s Android and Apple’s iPhone market, people are using countless apps everyday. And, most of them are selling right and left. Taking the time to develop and sell a smartphone app may be worth your while since it’s a very lucrative way to earn money online. The apps cost almost nothing to actually develop and don’t involve any shipping or storage costs, which works to expand your overall profit margin. Well performing apps can make thousands in ad revenue each month for their creators, making them another great passive income strategy.
Find a profitable niche. Starting with your interests, write down as many niche ideas as you can. Think about topics people might search online. Ideas include passions (like surfing or body building), fears (like spiders or speaking in front of crowds) and problems (like getting out of debt). Do keyword research to see it others are interested in the topic. Find out if a domain name is available that matches the keyword 100 percent. 
Then once you’ve got your domain name and hosting sorted out, it’s time to pick a CMS, or Content Management System, that will let you update pages, build your blog and integrate with all the other services you need. It’s hard to go wrong with WordPress—the CMS powering close to a quarter of the internet. Keep in mind that eventually as you start growing traffic to your blog, you'll be wise to invest in a managed WordPress hosting plan, where all of the settings are custom-tailored and optimized to work particularly well with WordPress-powered websites.
Sites like Qmee offer you the chance to search and conduct your everyday activities on the Internet while also earning money. In effect, you get paid to search online across sites like Google, Amazon, eBay, Yahoo and Bing, with countless sites offering your the ability to earn money while their software is listening in on your activities in the background. A little creepy? Maybe.
When was the last time you went to a new restaurant without looking it up online beforehand? Or bought a product that didn’t have at least a few 5-star reviews? It seems like more and more our world is run on reviews. And you can make money online by writing them. Get started by creating accounts on sites like Vindale research, Software Judge, FameBit, CrowdTap, Influence Central, and Modern Mom. However, before you run off and start writing, be sure to check the small print on each of these sites. Writing reviews isn’t a huge source of guaranteed income and you want to make sure that it’s worth your time before you get going.
E-books represent about 20 percent of all book sales in the U.S. The good news is you don’t have to be a publisher with deep pockets to get in on the action. As a solo internet entrepreneur, you can sell ebooks directly from your own website. You can sell your own works or sell a public domain work. Simply upload it to your website (or seller account on Amazon) and start publicizing it on your social media platforms, on your email list, your blog, website, etc.
There are numerous printing companies that will print your designs onto not just T-shirts, but also hoodies, hats, posters, cushions, bags, and phone cases, to name a few items. These businesses also offer fulfillment services. This means that you promote the merchandise on your own site and once you sell a product the printing company will not only print your design but also send the item directly to the buyer. So all you have to do is concentrate on the marketing and selling of your products, and the fulfillment company will take care of the rest.
Here’s a good example of how lead sales can work in real life: My second website, Life Insurance by Jeff, brings in a ton of traffic from people who are searching the web to find answers to life insurance questions. While I used to have the website set up so I could sell these people life insurance myself, it was a lot of work to process all the different requests and clients. As a result, I started selling the leads I gathered instead.