Not feeling particularly bright today? Get a mental boost for the day, or for a lifetime, by firing up iTunes U or TED, a couple of applications for smartphones and tablets that put the world’s best minds to work for your personal enrichment.

Apple Inc.’s iTunes U app provides free access to what Apple estimates are 500,000 lectures, books and other materials from university-level courses at such schools as Harvard, Yale and Oxford.

The introduction to computer science course from Harvard, for example, is a comprehensive 87-part package including the syllabus, video lectures, notes, problem sets and computer code taught by senior lecturer, startup founder and computer forensics expert David J. Malan.

Or perhaps you’d rather restart your education at Yale with the financial markets course by an esteemed economist, Robert J. Shiller. The 12-week, 23-lecture course was recorded on campus in the spring of 2011. Follow it at your own pace, over a few months, or over a weekend.

You can sync courses among devices via an iTunes account. There’s no degree in it for you, but there are no tests, either; just free smarts.

TED, the free app by Ted Conferences, for Android and Apple, is a trove of hundreds of short, riveting lectures and presentations given during Ted-branded meetings around by the world by artists, scientists, philosophers and other thought leaders on subjects as whimsical as “why videos go viral” and as counterintuitive as “saving for tomorrow, tomorrow.”

What sorts of things can you encounter in Ted Talks? There’s the video of Abigail Washburn’s eight-minute presentation on “building U.S.-China relations — by banjo,” or Jean-Baptiste Michel’s talk on “the mathematics of history.”

Search for subjects that interest you, or tap “Inspire Me” to set up a timed list of offerings in categories like “courageous,” “funny” or “jaw-dropping.” If you don’t want to watch the lectures on video, tap the “listen” button to begin the Ted Talks feed that plays one presentation after another.