There are loads of incredible options in 2018. These are the ten I truly believe that riders will enjoy the most for years to come. Keep in mind that electric bikes are the only bike market that is still growing! There is going to be more and more interest in these in the coming years which is going to drive up the value of your bike if you invest early.
An anti-theft radio GPS that mounts to standard bottle cage bosses and can locate within 9 feet, it runs on the Verizon network and costs $5/mo in addition to the hardware. Integrated vibration sensing alarm sends an automated text message alerting you anytime the bike has been "locked" using the companion smartphone application (Android or iOS)...
There are individuals who claim to have lost considerable amounts of weight by using an electric bike. A recent prospective cohort study however found that people using e-bikes have a higher BMI. By making the biking terrain less of an issue, people who wouldn't otherwise consider biking can use the electric assistance when needed and otherwise pedal as they are able. This means people of lower fitness levels or who haven't cycled in many years can start enjoying the many health benefits E-bikes have to offer. 
The first regularly produced device resembling the modern bicycle was unveiled in 1818. It was called the Dandy Horse. The two-wheeled ride-on Dandy Horse was the brainchild of German inventor Baron Karl Drais, and it featured a handle bar, a padded seat, and two inline wheels of nearly equal size. What it did not feature were pedals; this was a "running machine," thus its name in German, Laufmachine. The Dandy Horse saw only a flicker of popularity, and was largely an historical footnote within a handful of years, though its design is nearly mimicked in the child's balance bike of today.
Because e-bikes are capable of greater speeds for longer periods of time than standard bikes, you want extra control. Wider tires provide traction and some bump absorption with little penalty. You also want strong brakes to slow you (and all that extra weight) easily. It's worth looking at the quality of the brakes and investing in bikes with better ones if you can.