Bike-sharing startups have captured billions of dollars in venture capital, blanketing China and growing quickly in the U.S. and Europe. Now, the biggest players in China and a few U.S. upstarts are eyeing expansions into electric bicycles, which could help attract more customers who might want help riding longer distances or pedaling uphill.

Mobike, which has raised $928 million from backers including Tencent, is considering launching electric bikes, according to two employees. The company hasn’t yet decided when to launch e-bikes, in part because many Chinese cities have tough regulations governing electric bikes and scooters. While some cities allow electric bikes, others have banned them outright and even confiscated the bikes of some electric bike-sharing startups. E-bikes aren’t allowed in central Beijing, for instance.