A crop of new companies like PrizePicks are capitalizing on the demand, offering a sports-betting-like experience that falls outside of gambling laws. The tactic has drawn throngs of new users, including young adults and people who live in states where sports betting isn’t legal.

Atlanta-based PrizePicks, which has attracted new users at a fast clip over the past year, says it offers fantasy-sports games, not gambling, and that it only operates in states where its products are legal.

Over the past year, the PrizePicks app has been downloaded more than the sports-gambling apps for Barstool Sports and Caesars Entertainment, and it has been gaining ground on the top two competitors in sports betting, FanDuel and DraftKings, according to estimates by data tracker Apptopia.

The company’s ascent has contributed to growing tension in the fast-evolving U.S. sports-betting industry, where fantasy apps and gambling companies are pursuing sports enthusiasts who are new to betting. Fantasy-sports apps are increasingly making products that are similar to sports betting, but are more lightly regulated.

Fantasy sports have largely been considered by states to be a game of skill, requiring research and knowledge to be competitive. Sports betting is considered gambling as a game of chance.

Gambling is regulated state-by-state, with different rules governing sports betting and fantasy sports; some states haven’t regulated fantasy sports at all.

Some gambling regulators and rival companies say that PrizePicks’ model is making sports betting available to a younger audience, as well as in states where it hasn’t been legalized or regulated with consumer protections. In most states, sports betting has a minimum age of 21, while daily fantasy-sports games typically have a minimum age of 18. PrizePicks, which in March raised its minimum age to 19, said it made the change to keep high-schoolers from playing.

PrizePicks has built an avid fandom for its simple “pick ’em” style games focused on individual athletes. Customers build what PrizePicks calls an entry by predicting how several athletes from different teams will perform in a game. The prediction is whether each player will exceed or miss a benchmark set by the company, such as whether a basketball player will score more or fewer than 25 points in a game. The winning cash payout is known as a prize.