Robert Nay, according to venturebeat.com, built Bubble Ball (his first app) with a little help from his mom. In contrast, the suite of Angry Birds games has a staff of dozens and about 50 games out there.
Bubble Ball did 400,000 downloads on January 13 alone. All told, it's displaying on 1.5 million devices since December 29.
The game itself is moving a ball from one side of the screen to the other, using bare-bones resources like sticks or triangles. Nay's mom, Kari, had a big hand in developing the different levels.
Nay, according to venturebeat, used Corona SDK to get his app on Apple as well as Android.
Angry Birds is still the top paid app. It's the one with naughty pigs, suicidal birds and a sick amount of addictive-ness.