People love sharing their opinions on Facebook, and most of the time, we don't want to hear it. But there are some companies out there that want to know what you think or do or purchase. They're online surveys. Brands hire survey companies to find out what consumers are doing. And those survey companies get your opinion to pass along to those brands.

Survey offers are popping up all over the place. Both online and in the app store. But how do they work? And which ones can you trust?

Favorites are Swagbucks, Survey Junkie, Neilsen, Opinion Outpost and One Opinion. All of these work the same. You can visit their websites any time to see if there are any surveys available. There will be. If you want, they'll send you an email when a new survey is ready. But be aware, they'll fill up your inbox.

To give you some idea, I took a survey on Opinion Outpost. Before the survey begins, it asks for demographic information, age, gender, household income, employment field. This survey wants to know about recent home improvement purchases and which stores I regularly visit. After about 5 minutes of answering questions, I'm told I don't qualify for the survey.

It's the same for all the survey companies, they're looking for a specific demographic, and it can be frustrating spending time to answer questions only to find out you don't qualify and you were wasting time.

Surveys can take 10 minutes up to 40. You can expect to earn under a buck for most surveys but the longer the survey, the more you're paid. Some surveys pay $3. They generally pay out after you reach a certain amount, and the payouts are either gift cards, check or PayPal.

You won't make a living answering surveys, but if you devote a good bit of time to them, you could earn around $100 a month.

But be aware, there are survey apps and websites that aren't reputable that only want your name, address, phone number, and email address. So you'll do fine with one or more of these survey companies. These are surveys you can take while watching TV, waiting in line or just relaxing. Isn't it nice to know your opinion is worth something?