This may sound like an odd issue, however ever since I've had my Wii U I've been getting connection issues between the console and the gamepad. I've sent it in for repairs and they couldn't find anything wrong, however today after some messing around I noticed that having the default camera app on my N9 open with GPS/geotagging enabled caused these issues, every time.

Does anybody else with an N9 have a Wii U? If so could you open up the camera app with GPS on and see if you also get this interference? I'm trying to hunt down any possible sources for this problem.

I've concluded that when WiFi is enabled, interference occurs when the phone first boots into the home screen and it's looking for a connection and also when using GPS-enabled apps. Turning internet connection off solves these problems.

Is there any way I can disable 5GHz on the phone (as that's what the Wii U Gamepad uses), whilst keeping 2.4GHz active?

had the same issue before i switched to sgs4. never knew it was related to the n9. as soon i started using sgs4 instead of n9 the problem went a way and have been since

Excellent, thanks for confirming my suspicions! I was looking at getting a new phone anyways, this is just another reason to do so.

I wonder if any other phones have similar effects, especially the Lumia models.

first time hearing this. no wii u to test..

Can now def confirm n9 interfer with wii u. Writing from my old n9 now with the wii u tab next to me. Have not a single issue with wii u tab interence for months.
with the power up: 6 gamepad disconnects in 10min

Thanks for following up and confirming that I'm not crazy