What app or software can I use on my windows 10 computer(desktop) or iPhone 7 latest software to scan for interference as in another device effecting my frequencie of my Bluetooth wifi in a 2.4 and 5 hz range.
If by "desktop" you mean an ordinary PC, then you can get a (cheap) SDR dongle (see http://www.rtl-sdr.com/) and then you can use any of the SDR programs, preferably with waterfall display around suspected interference frequency. There are also some Android apps, I do not know about iPhone.
I have used SDR# (read: Software Defined Radio Sharp) on a Windows 10 desktop to scan for signals, while doing so seeing how the noise floor changes dramatically. SDR# uses the waterfall display to help visualize noise, which would help one who isn't experienced in these sort of things be successful. In one case, I used SDR# to identify a noisy power supply that kept me from hearing a distant radio source.
The effectiveness of SDR# is related to the receiver you're using. While I was using an inexpensive TV tuner receiver, the range of the very cheap receivers are not created equally, so shop around.
While outside the scope of your question, I would like to add that the fun that can be had with SDR in general can be addictive. There are better receivers out there and an inexpensive raspberry pi project can also be built to accomplish the same thing if you need a more portable solution.