I don't file taxes & only have a smartphone to claim my child for the stimulus check. Everytime I try, I am not able to view the submit button, so I have everything filled out to claim him, but unless I can actually submit it, it won't make a difference.
There are two different sites you can use to register. One is a TurboTax site and the other is an IRS site. Which one are you using? If one doesn't work, try the other. Can you either squeeze or expand the image on the screen on your phone to see the submit button?