According to the Nokia Developer Blog:
The company's strategy for success has involved delivering simple, clever apps that provide short bursts of entertainment. Apps like ‘Milk the Cow’, 'Talking Hamster’ and 'Flashlight Extreme' are Pico Brothers apps that deliver instant fun and utility. “We make the apps that people want to have,” says founder Niklas Karlström, “That’s given us momentum, and it’s snowballed.”
If you want to know where to start with the Pico Brothers's apps, have a look at Baby Sleep, Analogue Stop Watch and 101 Big Sound Buttons. Yes, many of the apps are novelties, but there's bound to be something in the hundreds of titles to take everyone's fancy. Which is why the Pico Brothers managed to get to the 100 million mark, with a mix of free, commercial and ad-funded applications. Well done again.