everywhere, from phoenix to miami and the deep south. they re zipping across the nation, along the way winning over fans. i would give them an a, definitely an a because they are reliable. reporter: and gaining enemies. people just ditch them or misuse them and so they kind of get in the way a little bit. reporter: they ve been called revolutionary by some. back to the future, you know. reporter: and unsafe by others. they re dangerous. reporter: graham, a west baltimore artist, say scooters are an easy way to get from point a to point b. check one of the four apps and i look at where the closest scooter is. i walk over, grab it, and take it where i need to go. reporter: baltimore started a scooter program last year and the department of transportation says it provides 45,000 rides a week. our goal is that it would increase access and it would provide more sustainable