Been frustrated with footpods, ant+ and using them outside my home. Took me an hour to get my laptop to use my phone hotspot via usb then I had to hook up an IPad as the laptop couldn’t be balanced on the treadmill, that required screen mirroring which doesn’t work perfectly as well. Then the foot pod couldn’t be discovered by the laptop even though it was listed as on and available in the network. Foot pods are fairly accurate at the speed you calibrate but if you run faster they tend to overstate speed.
So I gave up and tried my luck with this App, should have used it from the very start. Set up in 20 seconds, you can either type in your speed or use the accelerometer in your phone which is surprisingly fairly accurate, if anything it shows .2 to .5 k less than your speed but changing your hand movements can adjust that to make it more closely match. No Ant+, no footpod, $1.99 and never have to worry about batteries in the foot pod dying or a bad connection. You can run with it using an arm strap or just holding the phone which I prefer as I can adjust hand movement to capture speed even more accurately when it’s off a little. If you want perfect calibration and don’t want to hold phone while running you can just hit a + or - button and leave the phone on the treadmill.
P.S. One caveat, you need an Ipad to display the results from the IPhone, the app can’t do Zwift at the same time.