Dan Kurani is the co-founder and CEO of Thumb.

Easily the most talked about companies in 2012, Facebook and Apple, are no strangers to disrupting ecosystems in the tech world. However, despite innovating in almost every segment, including gaming, hardware, and web development, both have failed to make a dent when it comes to information discovery.

Apple’s hyped up voice-activated digital assistant, Siri, was declared a huge failure once users realized the application had under-delivered on its lofty promises. Apple even faced a class-action lawsuit based on the fact that Siri did not perform for users as advertised. Apple also recently backed away from music discovery by shuttering Ping on iTunes.

Recently Facebook demonstrated its weakness in discovery and search, by officially beginning to shut down Facebook Questions, which allowed users to poll and post answers from friends. Facebook Questions proved once again that the social network was trying to do too much, and its features suffered as a result. Facebook also hedged its bet on discovering photos from friends with its purchase of Instagram.

It’s clear that neither company has been able to find a singular solution to the search for information everyone finds themselves doing on a daily basis. But this doesn’t mean that its an impossible feat, companies like Google, Reddit, Yelp and Wolfram Alpha have gotten it right by creating specialized outlets for each type of information search. Services that are working have one thing in common; they reflect the decision-making lifecycle that the human brain uses to discover answers to questions.

Our brain is constantly seeking out information about the world around us, and this information falls into two categories. First is fact-based information grounded on existing data. These second is opinion-based information generated internally by individuals.

People have always turned to friends and family for opinions, advice or data in every phase of the decision-making cycle, but now people increasingly turn to the Web and apps when the time comes to make a decision. Facebook failed at information discovery because it didn’t realize a crucial point: people don’t always want the advice of their friends.

So which companies are winning?

In the preliminary hunt for research, Google is still the clear leader in getting you the best data for any question. Wolfram Alpha has also proven itself a leader in computational functionality, by aiming to give people a fact-based answer to a query.

For the more crowd-sourced response, look to Yelp, Quora and Reddit, which have evolved into top sources for consumer-generated information. These networks have proven the input of a community of strangers is often more powerful to consumers than something like Facebook Questions that poses queries to your real life social sphere.

This year, Quora has further established a thoughtful long-form Q&A outlet for people across the world. Yelp has proven a trusted and profitable resource for structured reviews from individuals about anything from lawn care to bars. Reddit has revitalized the cultural information space with its massive base of user-shared and generated information, with even Obama jumping on board to spread awareness.

You will notice that the most disruption is occurring in the opinion-based category. Why are more people turning towards the thoughts and opinions of others instead of trusted search engines like Google?

First of all, it’s hard to disrupt information discovery based on facts, as witnessed by Bing’s constant but mostly ineffective move at dethroning Google. Why? They have built on years and years of algorithms that have constructed the world’s largest databases of information. This isn’t something a startup can disrupt starting in a garage or school.

Another reason we are seeing more interest or opinion-based startups succeed, is that computational approaches, like Wolfram Alpha’s, lack any human element, meaning no way to get opinions, assessments, or the necessary judgment that are often rooted in knowledge, values, beliefs, and experience. This means people aren’t getting everything they need when they have certain questions. These personal elements are essential in helping people get guidance, create context for their thoughts, and make both emotional and non-emotional decisions.

Although database or search engine sourced information will always play an essential role in content discovery, consumer-generated information is a nascent trend that will continue growing in 2013. The growth of networks like Yelp and Reddit are proving that users want a more social approach to information discovery, especially towards the end of the decision making cycle. There may never be a single resource for information discovery across the entire decision-making process, but it’s a safe bet that consumers will continue seeking subjective input from other real people at a growing rate. Those that win in 2013 will have a real opportunity to become the go to service for advice from others.

Dan Kurani is the founder and CEO of Thumb, the mobile social network for instant opinions from real people. Prior to launching Thumb in 2010, Dan Kurani spent the last 10 years as President/CEO of Kurani Interactive, a multi-million dollar digital development firm that worked with Fortune 500 brands like Nike and Universal Studios.

Adam D’Angelo and Charlie Cheever founded Quora after leaving Facebook in its early days. The site is a slicker version of Yahoo Answers and allows multiple people to edit answers for helpfulness and accuracy. Quora hopes to gather as much information as possible to create a large database of information, similar to Wikipedia. The company competes with a ton of other question-and-answer services, such as the Ask Reddit subreddit, Ask on Google+, and even Facebook Questions.

The funding round came largely from the Facebook family. Facebook board member Peter Thiel led the round, and former Facebook employee and partner at Northbridge Venture Partners Jonathan Heiliger participated. Benchmark Capital also contributed to the round.

Founded in 2009, Quora raised $11 million at a $86 million valuation in 2010. Since then, it’s released an iPhone app to find location-specific answers.

Question mark image via Flickr user Michael Coghlan

In stealth mode for some time, Hipster first opened its gates for the South by Sotuhwest conference in Austin, Texas, where it received 4,000 signups to its site and 10,000 to its launch mailing list. Attendees to the conference could use Hipster to ask and answer questions about it — for example, “What is the dress code for SXSW?.” While the conference is over, its SXSW page has still been kept online as demo of its concept.

Founder and CEO Doug Ludlow, who previously started MadKast and sold it to sharing widget ShareThis in 2008, told TechCrunch that the company learned a number of things from SXSW. For one thing, it now plans to launch across every city in the U.S. as opposed to expanding by individual cities.

In comparison to Yelp and Foursquare, which operate in a similar territory while not directly offering question and answers, Ludlow said that Foursquare “provides a very poor web experience for accessing, augmenting, editing, or sharing [local information]” while Yelp lacks a good method for “submitting knowledge when it’s freshest in your mind (namely, while you’re currently at a location.)”

With the financing, the Los Angeles-based startup is planning to make the move down to San Francisco. Angel investors in the round included Mitch Kapor, Dave McClure (500 Startups), Lightbank, Charles River Ventures, Max Ventilla, TechStars, Don Dodge, Paige Craig, Ludlow Ventures, and Lerer Ventures.