Tools to help with traffic awareness are (in no particular order) -
Theoretically, the more of these tools you use the lower the risk.
I learned to fly 40 years ago and I understand the need for a good lookout.
The limitation is that by the time you see a conflict there isn't much time to react. Also, it's likely you're not always looking.
Effective radio communication is vital but obviously can't be used on its own.
This is the most effective form of electronic traffic awareness. It's accurate, real-time and most of all has high integrity.
It's limitation is that not many aircraft are ADS-B equipped depending on where you are in the world.
Also if you only have ADS-B OUT you still need another way to receive traffic.
Electronic conspicuity devices are the next best thing to ADS-B and much cheaper.
They are also accurate and real-time.
The limitation of EC is that much less power is used to broadcast; 20 watts compared to 250 - 500 for a mode S transponder. Also the internal antenna is far less effective and can be masked by metal in the cockpit.
Having said that, they seem to be very effective.
If you have ADS-B OUT but not IN, you probably need a portable receiver. There are lots of these to choose from.
The benefit of your EFB is that it's a perfect place to display traffic from all the various sources in one place and on a map.
That's why EFBs provide a mechanism for displaying trafiic from external devices. AvTraffic uses this interface for EFB integration.
There are two limitations of the internally provided traffic.
Firstly, it only shows other users of the same EFB app.
Secondly, it relies on a cellular connection to the internet. Fortunately, this is usually available in the places you most need it so it's actually very valuable.
This also relies on a cellular connection to the internet but it isn't tied to your EFB provider.
Again, cellular internet is widely available and will only improve in the future.
The main value of AvTraffic is to show traffic that isn't using the same EFB app as you.
The other valuable feature in AvTraffic is the ability to send audible alerts to your bluetooth headset. This has helped me on several occasions.
However, the ADS-B and FLARM traffic provided may be limited by ground feeder coverage in some areas. Therefore using AvTraffic in conjunction with an EC device or portable ADS-B receiver is encouraged.