Alarm clocks have the unenviable job of making us do something we typically don't want to do – hauling our asses out of bed every morning. But that fraught relationship leads to an interesting existential question: What does it mean to be a good alarm clock? Is it one that gives us what we want (more sleep) or one that gives us what we need (a forceful push out of bed in the morning). I don't know the answer to that question, but I do know that Wake N Shake falls squarely in the latter category.

It certainly isn't the first deliberately frustrating alarm clock. We've seen many variations on the theme in recent years, from apps that make you solve math problems to shut them up to the Clocky Alarm Clock, a wheeled specimen that rolls onto the floor and out of reach after one round of snoozing. That one was deemed innovative enough to warrant shelf space at the MoMA Design Store.

But Wake N Shake, which recently got a 4.0 upgrade and a fully redesigned UI, is especially strict, even among its bothersome peers. For one, it doesn't give you any way to delay your wake-up – there's no snooze function whatsoever. And then there's the task it demands for turning off the alarm. It's simple enough: you just have to shake your iPhone until you fill up an on-screen meter. But an idle twist of your wrist won't do. You have to pump the thing like you're trying to win the Martini-Mixing World Championships.

The app, admits developer Pedro Alejandro Wunderlich, was designed to "wake up people without mercy." Merciless though it may be, the punishment isn't random. "I think math and other brain-rekindling activities are OK at waking people up," he says. "We tested stuff like that ... We even tested a method that would scare you into waking up – you had to stare at the screen, and a random scary surprise would appear." Ultimately, though, his team found that the most effective way to get people up – and to make sure they stayed up – was simply to get their blood pumping. Hence the shake-o-meter.

It does have some other features, like a quick nap mode and a social wake-up component, which adds a dash of gamification to the morning ritual by getting you to compete for rewards with your friends. But even Wunderlich admits that the incentives have diminishing returns. "How do you remind a user of the rewards they could get when they're half-asleep and barely conscious?" The shake-o-meter, which can be adjusted to require varying levels of shake intensity, is efficient on a much more primal level.

Yes, that's right. The app comes stocked with an "Evil Laugh" wake-up chime.

It's fun to think of Wunderlich like one of those muscle-bound personal trainers, except for sleep. We're the snooze-loving wimps. He's not having any of it. The best alarm clock, in his mind, is the least forgiving one – because if you give us sleepyheads an inch, we'll take three 15-minute snooze sessions. "If there's a way to cheat it, people do," he says. "Sleeping a bit longer is almost irresistible, and in a half-asleep state of mind, we'll look for a way to stay in bed, no matter what. Kind of like the way we'd eat anything when starved."

To that end, Wunderlich and his team try to plug all the holes they can. Alas, he says, some innate limitations of iOS at present stand in the way of his vision of a totally inescapable morning alarm. After all, even if you can't snooze, you can always turn your phone off. Still, Wunderlich dares to dream. "A perfect alarm, for starters, would be one that's absolutely merciless without any holes to exploit."