There are two basic categories of electric bike, and their uses don't offer equal crossover value. The first category is essentially a normal bicycle that has been outfitted with an electric motor. These bikes are the same size as a standard bicycle, and handle almost identically, save for the obvious benefit of added motive power thanks to a motor and battery.
The Shift S1 isn’t going to blow anyone away with amazing performance, but it is peppy enough to have a lot of fun on. And if you mostly travel by rideshares like Uber or scootershares like Bird, you can probably pay for the S1 after just a few months of cutting out app-based transportation. It’s hard to ask for too much more from such an inexpensive e-bike. 

Electric Bicycles are defined by the California Vehicle Code [32][33]. In summary, electric bicycles are to be operated like conventional bicycles in California. There are several exceptions to this. A person must be at least 16 years old, and anyone riding an electric bicycle must wear a bicycle helmet. The e-bikes must have an electric motor that has a power output less than 1,000 watts, is incapable of propelling the device at a speed of more than 20 miles per hour on level ground, is incapable of further increasing the speed of the device when human power is used to propel the motorized bicycle faster than 20 miles per hour, operates in a manner so that the electric motor is disengaged or ceases to function when the brakes are applied, or operates in a manner such that the motor is engaged through a switch or mechanism that, when released, will cause the electric motor to disengage or cease to function.

"Motor-driven cycle" means any vehicle equipped with two or three wheels, a power source providing up to a maximum of two brake horsepower and having a maximum piston or rotor displacement of 50 cubic centimeters if a combustion engine is used, which will propel the vehicle, unassisted, at a speed not to exceed 30 miles per hour on a level road surface, which does not require clutching or shifting by the operator.[138] The designation is a replacement for "scooter" and "moped;"[139] Vermont doesn't seem to have laws specifically for e-bikes.[140]
"Bicycles" and "Electric Bicycles" are legally defined in the Texas Transportation Code Chapter 551., titled "Operation of Bicycles, Mopeds, and Play Vehicles" in Subchapter A, B, C, and D.[58] The following definition of electric bicycle was passed by the Texas legislature in 2001. "Electric bicycle" means a bicycle that is designed to be propelled by an electric motor, exclusively or in combination with the application of human power, cannot attain a speed of more than 20 miles per hour without the application of human power; and does not exceed a weight of 100 pounds. The department or a local authority may not prohibit the use of an electric bicycle[0] on a highway that is used primarily by motor vehicles. The department or a local authority may prohibit the use of an electric bicycle[0] on a highway used primarily by pedestrians.

However, Emu sells a little foldable number if that's your bag. The Emu Crossbar is for  town commuters that require a sweet ride that's backed up by solid Shimano Nexus hub gears and Tektro brakes, which are adequate if not the best on the market. Riding is smooth and easy, with the crank moving sensor doing its best to iron out any gaps in power delivery.
Bicycles offer an important mode of transport in many developing countries. Until recently, bicycles have been a staple of everyday life throughout Asian countries. They are the most frequently used method of transport for commuting to work, school, shopping, and life in general. In Europe, bicycles are commonly used.[67] They also offer a degree of exercise to keep individuals healthy.[68]

The federal Consumer Product Safety Act defines a "low speed electric bicycle" as a two or three wheeled vehicle with fully operable pedals, a top speed when powered solely by the motor under 20 mph (32 km/h) and an electric motor that produces less than 750 W (1.01 hp). The Act authorizes the Consumer Product Safety Commission to protect people who ride low-speed electric vehicles by issuing necessary safety regulations.[63] The rules for e-bikes on public roads, sidewalks, and pathways are under state jurisdiction, and vary.