Genie to Nighthawk app upgrade

C7000v2 Modem/router - Firmware 1.02.09 - Spectrum ISP

Sorry if this a repeat question.  I have my home network configured with 25 devices and using all ethernet ports and both 2.4 and 5ghz wi-fi bands.  All works fine with Netgear Genie on my windows 10 PC.  I was thinking about installing the Nighthawk app on one of my 2 android devices (a phone & a tablet).  BUT I'm worried that i may lose all the work setting up the current network (pc, android, a/v, printer, lights!).  Is it straightforward OR do I have to be VERY careful???  Any guidance would be appreciated!

Why might I install: I am worried that Spectrum will, in the future, cap internet usage and I want to start monitoring total usage [not by device]. Is the Nighthawk app "more efficient" than the Genie Traffic Monitor?

Thanks in advance,

John