How do I check whether my Wifi is working?

How do I check whether my Wifi is working?

I used to have no trouble sending photos to my smartphone using the camera's wifi. Recently this hasn't been working, with the the camera never getting beyond 'Start dedicated app on target device'. I've updated the Canon Camera Connect app, installed it on other devices and reset the camera's wifi settings but nothing has worked. Any suggestions as to what would be wrong?