Next wave of innovation in content aggregation? Part 1

I'm having hard time finding reasonable, thoughtful, musing or moving content online. When I say 'online' I mean my phone. I realized that I have been doing most of the reading on my phone now. Apps that I use to consume content on my phone are the following:

Flipboard: I actually hate it. I think the aggregation system is outdated (curating some articles from various well-known websites, this is not what I expect from a news aggregator), the only thing that I like about this app is the flip action. I think it's addictive. Resembles scanning through newspaper pages, feels natural. 

Facebook: I'm constantly checking my Facebook newsfeed. I cleared it out of unnecessary 'friends' and 'likes' a year ago, it's working out great for me. Most of the content is relevant, but (sadly) ephemeral and/or popular. Currently Facebook offers me a broad, casual content, but nothing more. 

Paper: This is another Facebook app that I use for content consumption. I think it's a beautiful app, offers a unique experience; resembles Flipboard in that sense. Two flaws with this app (1) it's replicating some central features of Facebook app, such as notifications. I believe the main motivation here was to use these notifications to re-engage users into the app, (notifications are pushed to my lock screen after using the app, which gives us a hint regarding the built-in 're-engagement' scheme) .However it's an app designed for reading (named 'Paper'), not an app for social interactions (that's Facebook app). This creates ambiguity in the eyes of the user, which is not good. It's quite slow for social interactions anyways, takes 3-5 seconds for the app to load a comment. (2) Paper offers mainstream, ephemeral content, just like Facebook app it remains broad and casual. So why have an app like this, if it's not offering anything new other than design?

Twitter: I'm not a frequent user of Twitter mobile app. The mobile experience is really transient, looks like a stock ticker IMHO. I believe this is done in purpose; mainstream consumers demand fast consumption of content, fastest way of consuming content is Twitter right now. It also makes sense if your main aim is to generate impressions and inventory for ad sales. I'm not interested with that kind of content, in this case my indifference is acceptable.

I use Twitter on desktop to discover people, especially SMEs in certain subjects. I believe that open structure of the platform makes it the perfect testing environment for reputation graph. Twitter is a great tool if you know how to use it - it offers a chance for in depth analysis; let's you find rich and deep content, actually shows you a timeline of content evolution (I will talk about this matter in depth later on).

Quora: Quora is ... a great product with lots of flaws. I love the content in Quora, but hate the way they 'represent' that content to their users. I don't like their website UI (had my share of criticism, here is a long Q&A on the issue), their mobile experience is even a bigger mess. I believe that due to the quality of content and effective caste system that is imposed on users, people continue using Quora. Main reason that I criticize them is their sluggish approach to design innovation. They've raised loads of money, they should focus on giving the user a better experience with the content. 

Among all the apps mentioned here, Quora and Twitter differentiate themselves by offering resilient, (somewhat) timeless content. Users have a motivation to revisit the content, like reading a phrase from a book they like, or to fine-tune their knowledge on a certain subject. Second part is the part that interests me. My hypothesis is as follows: while learning something, people follow certain patterns through content. Certain patterns are deep rooted in learning, creating the backbone of any specialization; actually these patterns are easy to decipher - they are engraved in our education system. There is a certain pattern that you can see in the college curriculum which enforces certain kind of hierarchy on the way we consume content for a certain period of time - you could not / shall not read Calculus II content before Calculus I, learning follows this certain path. If you do, you will miss certain key points, not able to connect the right dots - at least most of us won't be able to.

Does content ordered in a hierarchical order really facilitate learning? Do we have any live examples? I believe the recent wave of e-learning startups are following this trend: Khan Academy has a catalogue of content aligned around education levels, Coursera copies the course system of universities, Udacity follows a similar pattern offering a catalog of courses, asks you to follow a path and earn skill badges (which resembles Diablo 3 skill tree). I learned coding HTML, CSS through W3 website, which asks you to follow certain steps, got into advanced topics Other tools that I used in the past such as Codeacademy, Treehouse have innovated 'learning patterns' for coding. 

What is missing here? What kind of content is not aggregated in an orderly fashion for learning?