(Reuters) -Bumble forecast its first-quarter revenue below analysts' estimate on Tuesday, signaling that the dating app operator's efforts to boost growth is taking longer than expected, sending its shares down 11% in extended trading.

Online dating apps have been grappling with declining user engagement and customer spending on their platforms amid lack of new features and still-high inflation.

Bumble's total average revenue per paying user (ARPPU) decreased to $20.58, compared with $22.64 a year ago.

Total paying users for Bumble app were at 2.8 million, down by 57,000 from the third quarter.

Earlier this month, the company's bigger rival Match Group, which offers dating app services such as Tinder, Hinge and OkCupid, also forecast its first-quarter revenue below estimates.

Bumble expects its first-quarter revenue to be between $242 million and $248 million, below analysts' average estimate of $256.9 million, according to data compiled by LSEG.

The Austin, Texas-based company's fourth-quarter revenue fell 4.4% to $261.6 million.