The market for electric scooters is booming, with companies like LimeBike, Spin and Bird appealing to consumers in big cities who are looking for quick, convenient and environmentally friendly transportation.

Investors are pouring money into these companies, especially as public transportation woes snare urban consumers. LimeBike and Bird have both pulled in over $100 million in funding, while earlier this month, Uber acquired Jump, which offers both bikes and scooters.

Users call up an app to find a scooter nearby and unlock it. When the rider is done, the scooter can be left and locked anywhere. Depending on the length of time a user needs them, the scooters are also affordable: LimeBike, Bird and Spin are rentable for anywhere between 15 cents and $1 per minute.

In the last few months, these scooters have popped up everywhere — but not everyone is on board with their growing popularity. Last week, a headline in The Wall Street Journal blared that San Francisco was being "terrorized" by the trend.

Indeed, a casual stroll down San Francisco's Market Street offered glimpses of unattended e-scooters on virtually every block. While commuters have embraced the ease and convenience the e-scooters provide, their ubiquity has been met with grumbles and, in some cases, government intervention.

Recently, the San Francisco City Attorney's office slapped cease and desist letters on all three major e-scooter companies, taking them off the streets for now — but the companies are still attracting interest from investors.

As funding and consumer interest grows, companies are anxious to get their vehicles back on the road. In the coming weeks, San Francisco's Municipal Transportation Agency should notify companies when electric scooter operators can resume business.

For now companies like Bird, Lime and Spin are applying for permits to operate under the one-year pilot program in the city. Back in April, Bird CEO Travis VanderZanden, who is also an alum of Uber, issued a letter supporting more oversight.

Bird "applaud[s] city officials efforts to work with us in ensuring that we can bring environmentally-friendly transportation alternatives to San Francisco, and we support... legislation to regulate e-scooters and are eager to continue the conversations around these regulations," VanderZanden wrote.