There's something about technology that actually solves a problem. All you have to see is a demo, and then it burrows into your imagination and nags at you until you own it -- particularly in times when it would have been convenient.

"Ah, if only I had TiVo, I wouldn't have missed this show!"

"If only I had downloaded Uber, I wouldn't have just spent 20 minutes in the rain looking for a cab!"

If you're even remotely an early adopter, you know what I'm talking about.

So yesterday, as I was supposed to be filing a story about the launch of a new app called Cover, I couldn't help but wish I not only had the time to write it, but that I actually had it on my phone.

Cover is simple. It's a contextually-aware lock screen that shows you the most relevant apps when you are likely to need them. It launched in beta yesterday.

I was stranded at the airport in LA for five hours with a baby. My laptop was dead, and there were zero chargers to be had. All I had was my phone, and one hand to use it while I soothed a teething baby.

The nag: Wouldn't it be cool if the top apps that I could use while stranded in an airport with my baby were automatically surfaced?

The Virgin app would be right there. Some other flight tracking app. Yammer, because I'm trying to communicate with my team. Wordpress's app, because I'm working remotely editing stories. Maybe Dots, because I'm bored. No scrolling through screens and experiencing that "What app was I looking for again?" blindness. When I landed, Uber would surface, or another ride sharing app, or Waze to check on traffic patterns. Maybe the weather app showing me just how cold it was in San Francisco too.

There are two problems with that little fantasy amid my horrific travel day. (Aside from how lame it is, as fantasies go.) The first is that Cover isn't quite that good (yet). It just does work, home, and car so far. The second is that downloading the app would entail me actually switching to Android. And even my fantasy 2.0 version of Cover doesn't quite warrant that dramatic of a life change.

Still it's the first demo that's made me think about wanting an Android phone. And considering this is something that three guys built in a matter of six months... well, let's just say I'm keeping my eye on Cover.

What Cover's founders get is the simple yet powerful use of context. I am constantly rejiggering what's on my first screen, because different apps matter at different times. Cover knows if you are at home, so it shows you a picture of your baby on your lock screen and pulls up apps like Sonos, Nest, or, say, a baby-tracking app for easy clicking. At work, it may pull up Yammer or your work email. In your car it might pull up Pandora and Waze.

Some of the coolest parts about Cover's technology is how it knows this. For instance, it didn't want to drain batteries, so it doesn't rely on GPS to know you are moving. Instead, it uses the phone's accelerometer and gyroscope.

And it has some pretty touches. You can hold and pull to "peek" behind the lock screen without actually unlocking your phone and drill down on your most context-relevant apps. The animations are more iPhone-like than snobs would expect. It also has some smart settings, so, say, your phone doesn't ring if you are home and it's after 10 pm. (There's a video of it here.)

As you play with it, you realize it's an app that's very well thought through. And part of that is because it's so limited. The team originally wanted to build a more immersive "launcher" like Facebook Home, but took the advice of its angel investors to focus on "just" being a better lock screen. "That's so simple, it can be universal," says co-founder Todd Jackson. "It will work in China and it'll work here." Those investors include Josh Kopelman via First Round Capital, Max Levchin, Scott Banister, Michael Dearing via Harrison Metal Capital, Charlie Cheever, Keith Rabois, and others. The company has raised $1.7 million to date. [Josh Kopelman is a personal investor in PandoDaily as well.]

Jackson was previously a product manager at Facebook, where he drew a lesson from what Facebook Home did wrong. It was too invasive, he says, taking over your phone and shoving Facebook at you. Cover itself, by contrast, fades into the background as it focuses on bringing your most beloved relevant apps to the forefront.

Cover is square in the middle of a trend I've written about a few times: Apps are no longer relegated to funny games and time wasters. They are slowly taking over the phone's most core utilities and doing them better. We've seen that in maps with Waze and Foursquare. We've seen it in texting and messaging all over the place. And with Cover we see it with the basic lock screen -- the most fundamental part of a phone's out-of-the-box OS you can imagine.

And of course, this is why it's only available on Android. Because the iPhone would never allow developers to do this. Android could also allow future cool features, like allowing Cover to sort your text messages and alerts according to context and priority. I would love if a text from my nanny showed up as a priority to a million other push notifications. Think of it like a Google Priority Inbox for all your other communiques -- only one that knows what is most relevant right now based on where you are. Jackson even suggested a feature where your spouse could update your wallpaper, to a picture of, say your baby taking his first steps as it happened.

Cover in its basic version is cool. But what Jackson wants to do -- and Android lets him do -- starts to fundamentally change how we interact with our most important digital lifeline. That's simple in concept, but not trivial.

Jackson himself admits he only started using an Android phone when he started this company, and if he weren't, he'd probably still be using an iPhone. That's less because iPhones are that much better and more because the culture of Silicon Valley is so iPhone dominant.

To the point that a lot of investors turned up their nose at Cover -- despite the surging Android usage numbers and the fact that so few companies are designed Android first. Jackson would ask VCs if they had Android phones, and they'd say "Yes! Of course!" before admitting they were somewhere buried in a desk drawer.

Jackson wonders what more investors have to see to be convinced that Android first isn't a losing strategy. "We've seen so much data!" he says. "Path is the most iOS company you can think of and it has more users on Android. I just believe in the numbers."

Valley investors increasingly aren't reflecting the smart phone make up of the world. And that's good for Cover -- the fewer of these guys funded, the less competition. Another big advantage is in jockeying for developers. Android developers are (comparatively) the red-headed step children of the tech world. "Think of a company like Square or Path," he says. "It must suck to be the Android guy there." His message to them: Come to a place where Android is all we do. It may not convince someone to give up Square-like-equity, but any edge in hiring is welcome these days.

Of course, there are the usual challenges to an app so seemingly basic and utilitarian. How can it possibly make money? Can it survive Android's much-stated fragmentation issues as it grows? And are Android users likely to be early adopters of something as wonky as a new lock screen?

Furthermore, plenty of people argue that Android's fragmentation and other challenges make an Android-first proposition too challenging, labor intensive and expensive. But in six months, with three guys, and less than the money it took to launch this blog, Jackson has proved those nay-sayers wrong. Cover may still fail, but it wasn't too hard or expensive to launch.

As with any startup, there are a myriad of ways Cover could remain a footnote in history as Silicon Valley finally starts to turn its attention towards an Android-first world. But Jackson's insights that Android-first apps are overdue is spot on. "The numbers always felt big, but everyone around us was always using iPhones," he says. "Those billion Android users aren't just in Asia. That crossed a line in the fall of 2011, and it's so obvious it's never going back,"

[Image courtesy Uncalno]