I am new to the RC hobby and am looking for a low cost controller with GPS or in which a GPS module can be attached later.

I came upon this one: http://www.rcdhamaka.com/index.php?main_page=product_info&cPath=1_103_129&products_id=2011

In openpilot.org there is a Openpilot REVO platform. What exactly is this board? I am not getting much information about this board elsewhere on the internet. Is it possible to connect a GPS module with this one? Any experience about this board?

Cc3d fc here does not work for gps tracking. Gps will be only for telemetry.

Cc3d board is the basic flight controller board from openpilot - which has no autopilot modes even though a GPS module can be connected it is only used for telemetry data.
Where as the revolution platform is the high end autopilot from open pilot REVO supports GPS based flight modes such as position hold, return to launch and waypoint navigation.
But revo platform is costly and not easily available. Anyway if you say what all requirements you need, I can suggest the best suited flight controller for you.

Thanks a lot !

The link that I posted says "CC3D EVO" whereas the openpilot site mentions about "REVO". That's confusing to me. I guess the board is not Revo. But I can't find out what its features are.

Anyway, my primary purpose is attaching a GoPro type camera in the quad, with or without a gimbal. So stability should be a feature. Also in the future (or even now, if budget permits) I want to have GPS autopilot and waypoint marking. FPV, if possible..but that's not an essential requirement.

Given these requirements, what should be the best flight controller? Budget is of course an issue...so if there are more than one options, please list them in accordingly.

Thanks in advance.

APM is the only option at present , that satisfies all your needs. You can get the complete kit for less than 8000.
You can also consider the tarot zyx-m flight controller which I think is good from all the reviews.

Is this cc3d evo any better than regular cc3d?It does come with some additional stuff in kit than regular ones?I am not referring to cc3d revo,but evo!
http://www.rcdhamaka.com/index.php?main_page=product_info&cPath=1_103_129&products_id=2011

What is the Antenna pedestal set ,included in the kit,for?

I figured it myself ,thought like sharing the info.

Evo , "WIth a function of being directly plugged into the satellite receiver(It needn't conversion cable).

Satellite jack means...GPS?

this jack is for satellite Receivers like orange satellite recievers....Not GPS