Is there a way to track wifi usage by app (iPhone 6)?

I just got an iPhone 6, coming from Android. I work at home so my ISP connection is vital. Many times I'll be working and my connection slows way down. Speedtest.net and some simple pings to Google show latency of up to 1.5 seconds, which makes work impossible. Normal ping time is 20ms. The problem is intermittent and very frustrating.

To troubleshoot, my ISP recommended that I turn off all devices and laptops in the house. Once I turned my phone off the problem stopped. Is there a way/app to monitor Wifi usage by app? A quick google turned up Onavo Count app that seems to do what I wanted, but when I searched for it in the App store it didn't show up.

I do have Dropbox loaded on my phone so I can easily back up my pics and vids to up to my local server, I disabled the Camera Upload setting to see if that was it, but I still get the problem periodically.

Poking around at other relevant settings, I do see these:

iCloud Photo Library = disabled

My Photo Stream = enabled

Thanks.