I just bought advanced phantom 3. I hear stories of people lossing it by going too far and battery dying and so on. What pre-caution do I have to take ? How can I take care of my drone? also are there any insurance for drones ? what are trackers ?

You have a number of questions there and all of them can be answered by reading the threads in this forum, have a bit of a look around.

Hey there!

Spend $50 on a "toydrone" that wont matter too much if you hurt (and it's hard to do) and if you do, you can learn about the bird by repairing it.  I know so much more about what's going on in my prosumer and pro UASs because I have spent time soldering on $4 motors or $12 flight boards or hell even $2 props.

I would learn how to fly a cheap "toydrone" first and then go fly your DJI P3A.

I mean I understand the desire and there is nothing I will say that will stop you probably but this is the better route IMO.

Don't get me wrong, the DJI birds are SUPER DUPER rediculously easy to fly which is what makes them so great and wonderful for photography so you can concentrate on the things that matter rather than how fast it can bank a turn or how many flips it can do.

What you have there is a fully functional flying apparatus and it can hurt someone or yourself so learn how to fly in an area that's open, and know your local laws and use common sense.

As for the questions you asked exactly 1) I don't know where you heard stories about people losing their bird because of battery.  The intelligent battery, coupled with the GPS and app functionality makes it so that you have to be the biggest idiot in this hemisphere to lose your bird because you ran out of battery. 2) Pre-cautions?  Well there are plenty and we touched on some macro ones but to target your bird specifically, watch the videos that tell you just what the pre-checks should be. (IMU, firmware updates, compass calibration, Failsafe set-up etc). 3) Yes, there is insurance for drones.  Google "Drone Insurance". 4) The word "trackers" is generic but it generally means something that can track. Often people will use third party tracking devices such as Trackimo on their bird in case of a downed or lost craft that doesn't have GPS.  It's a failsafe among other things.

Good luck and don't kill anyone.

This is also one time to RTFM (read the f***ing manual). It's not a $20 toy, but a complex piece of gear. You read the manual, try basic functions and then build on your knowledge and skills. Otherwise you'll be another guy posting YouTube videos "Hey look at me, I crashed my quad".

eldreds Posted at 2016-2-10 05:03
This is also one time to RTFM (read the f***ing manual). It's not a $20 toy, but a complex piece of  ...

Roger this statement.

Got to agree with Geebax.  If you really want some pointers,  make the effort to read the manual and this forum.  Most every mistake possible to make has already been made and discussed on here.  It is fun and interesting to read some of this stuff anyway.