Why do you need Shimano Di2 Wireless Kit?
Shimano released a E-tube App for Android / iOS user in April 2017. E-tube is an application enable user to diagnose, update as well as re-configuration your shifting patterns. (Semi synchronize, Fully synchronize shifting).
Fully Synchronize shifting
This function automatically shifts the front derailleur when the rear derailleur is shifted, allowing the derailleurs to work together efficiently.
Fully Synchronize shifting
This function automatically shifts the rear derailleur when the front derailleur is shifted, allowing the derailleurs to work together efficiently.
You can download E-tube app here
What else?
Wireless unit kit also enable user to connect their smart cycle computer (Garmin/Wahoo/Bryton) whether it has Bluetooth or Ant+ band connectivity, Shimano Di2 wireless kit enable you get a current gear data for analyze personal performance.