The GT-511C3 was launched in April ,2013.
The GT-511C1 was launched in May, 2013.
In June, 2014 the GT-511C1 was upgraded to GT-511C1R that is able to have 360-degree recognition.
The GT-511C Series was retired and replaced by GT-521F series in 2018.
The GT-521F32/F52 was launched in June, 2017.