Holy Stone HS100 may be the best drone with GPS function and FPV camera well worth the price under $300. 

What awesome features of flying make it so outstanding as a perfect quadcopter?

First of all, a high-tech GPS system is built in the control center of HS100, 

which is quite effective to enhance the flying experience by the interesting features come with it.

One function of these interesting features is Return To Home (RTH) function, 

which includes three kinds of returning home: Smart Return To Home, Low-Battery RTH, Failsafe RTH.

Smart Return To Home function, by pressing the button, your drone will fly back and return to the point place where it takes off.

Low-Battery RTH, it's a automatic function triggered when the flying drone's battery level is low, 

and the drone will fly back to where is about 100 feet away from you, 

you can still control it by pulling the throttle down to land to a safe area. 

When the power of the drone is complete empty, the drone will return to the Take OFF point where you set.

Failsafe RTH. When the drone lose the signal of the transmitter, you are unable to control it to return, 

don't worry, Failsafe RTH function works now,  the drone will also flying back towards to the Take OFF point until you get the control again.

As you can see, by the effect of the RTH function supported with GPS system, you will no longer worry about the possibilities of flying loss. 

And the Follow Me Mode function also provide another joy of flying. 

When this function is active, you can leave your hands away from the control, 

and the drone will follow to the GPS in your smartphone to follow you wherever you go.

Another thing to keep in mind about the Holy Stone HS 100 is that it is compatible with 3D VR, 

and it comes with a 720P 120° FOV FPV Wifi camera which has an adjustable angle to give high-quality videos and pictures, also providing the real-time viewing.

HS100 is power by the modular intelligent battery with a voltage 7.4V and a capacity of 2500 mAh. Depending on the charging power, it can take anywhere between 3 to 6 hours to fully charge your Holy Stone HS 100.