Yes interference is the big problem on 2G4, down load a wifi analyser app onto your device and check the area you intend to fly . I use wifi analyser pro (from play store) you will be surprized how many signals there are even in the middle of a big park hold your device infront of you and do a slow 360 degree circle. You will see the signals rise and fall as you turn. This will show you what direction the signal is coming from, fly away from the signals not towards them. Try and use the app to find areas that are wifi quiet.
Hope this helps

Just installed wifi analyser pro, going to test tomorrow. Thanks for the tip!...

WiFiAnalyzer (open-source)  best 1 free no adds
Optimize your WiFi network using WiFiAnalyzer (open-source) by examining surrounding WiFi networks, measuring their signal strength as well as identifying crowded channels.

WiFiAnalyzer is under active development by volunteers.
WiFiAnalyzer is free, has no-ads and does not collect any personal information.

Good job spanners.

I can't find an app like this one for iOS

hallmark007 Posted at 2017-8-22 15:20
Good job spanners.

not spammer i just use it and it works just sharing coped that from google dont get it do what you want just trying to help

Thats why I am in general not unhappy, our drone flies in 5,8GHz @ default.
Till now much less used. If only the otg would work for everyone and always (DHI, someone reading ....?)