LastHistory Mashes Up Your Music and Photo Timelines

You would hate my iPod. But not because my taste in music is bad. It's actually quite good. (Don't take my word for it, though. Judge for yourself.) But rather than rely on recognizable groupings like "Indie Electronica" or "Party Mix!!!," my iPod is chronologically ordered, like an audio diary. The playlists on it are primarily for the benefit of my nostalgia. The songs on "2006-03-March," for example, instantly evoke early spring, redwood forests, and a road trip down the California coastline. For a list-obsessed, memory-challenged individual like myself, a temporal playlist is the perfect way to travel back in time.

Thanks to LastHistory, my brain, already enfeebled by technology, is about to yield even more control to computer algorithms. LastHistory is a desktop application for the Mac that links up with Last.fm, a Facebook for music snobs. The site keeps detailed records of your music listening history, and LastHistory pulls in that data to create a spectacular visualization of your audio timeline. The result looks a bit like a decoded genome, and has probably just as much metadata powering it.

It's pretty to look at, but LastHistory's real innovation is in automatically syncing your listening history with your photos, which are also time-stamped. As a result, you can instantly create a slide show scored by the songs that dominated your headphones when the photos were taken. Justin Timberlake's "SexyBack" might bring you right back to 2006 as photos of a graduation party fade in and out. In other words, I no longer need to create a playlist for "2010-03-March"—LastHistory will do it for me, and also rope in the photos I take this month.

LastHistory is a neat tool, but it also demonstrates a key Silicon Valley business strategy: open up your data. The latest, hottest tech companies, including Twitter and foursquare, encourage use of their application programming interface, or API, which lets outside developers tap into the organization's data stream. Last.fm has been doing this for years. It's in part a marketing strategy, stimulating the creation of cool products that help spread word of the site. It's also labor outsourcing. Apple's iTunes store offers at least a dozen high-quality mobile apps for accessing Twitter on your iPhone. Not a single one was made by Twitter itself.

But I'll let the über-geeks worry about XML streams, UTF-8 encoding, and APIs. I'm just going to boot up LastHistory and let Phoenix's "1901" remind me what I did last summer.