Three months ago, Steven Howse struggled to pay rent. Now, the 32-year-old developer is trying to keep his hit videogame running smoothly as it pulls in more than $100,000 in revenue daily.

In “Slither.io,” snakelike creatures compete to gobble up food. The free multiplayer game leapt into the top 10 most-downloaded apps alongside stalwarts such as Facebook and YouTube soon after launching March 25 on iOS and Android, fueled by word-of-mouth from social gamers.

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