Verykool i119 - Manual (Page 10)

4
Battery Use
First time charging must be done using the
regular charger and not using the USB cable.
During the first 3-4 charge sessions, charge
the battery until it has been fully charged
according to the battery level indicator. This
ensures higher battery backup and extends the
battery life.
Avoid partial charging. Wait for the battery to
discharge completely before charging it again.
Use the device in vibrating mode only on rare
occasions.