Yes, LG K9 Candy does have the removable battery.
LG K9 Candy has Qualcomm Adreno 304 GPU. Which has a frequency of 400 MHz.
Yes, LG K9 Candy does have the GPS support.
No. LG K9 Candy does not have the front camera LED flash but it does have the display flash. Which helps to take a good selfie during low light conditions.