Hello!
I am fresh Phantom 3 pilot from Croatia (EU).
I buy Phantom 3 Advanced before 5 days.  He have firmware v1.3.20. I read on this forum about a problem with latest firmware v1.4.0010 (fly away, lose control etc.). There is no answer is it occasional situation or not? I am afraid to update my Phantom because is to expensive to crash it because of insecure firmware.
Do we have some fresh information about this problem  and will be new update?

Welcome to the forum, @croastro! Feel free to update the firmware to the latest available on http://www.dji.com/product/phantom-3/download
I am flying my Phantom 3 for more than two months and already updated two firmware versions to the latest official v1.4.0010 - no issues, no fly aways, no crashes, no jello, no rush - just read the manual careful. Also before update you should read the firmware manual too, because there are specified which devices have to be updated - the latest firmware include update just for the aircraft and battery.

Once you read the manual, I am sure you should know what you are doing and will fly safe and more informed.

just my 2 cent
edit: Yes, the lates firmware is _secure_

I and my others have upgraded the firmware more than once without any problems.  I will gladly upgrade when another firmware is available.  There will always be some horror stories, and of course, they will standout.  I am willing to believe- for every bad situation, there are hundreds of successes.

I personally have NOT gone above 1.04.0005.  Until someone gives me a very good reason to. That firmware version works best with the SDK apps that are available. I prefer Ultimate Flight over Litchi for now, I think UF is better implemented and has more settings and features.

Than you all. I will try

Please let us know how it went!