I do a lot of work on very large Wi-Fi networks (i.e. hotel/apartment complexes with 80 to 500+ access points), for a very rough quick test of coverage quality and roaming performance, find a Ping app for your phone that allows you to set a super low interval (i.e. time between pings sent), and ping your gateway router (i.e. 192.168.1.1) and while that is running walk around your home/location. It’s important that the Ping app keeps sending pings even if they drop, i.e. it should just look like a waterfall/constant stream of fast pings that show you red/green pings and ideally a summary at the end. On iOS the app I tell people to use is called “Ping” with a blue icon, I usually have to share the link to the app as there are several with this name (I’m not on my phone currently or I would share the link) there are several ping apps that do offer this fast ping feature.