+1 on this one... I've mentioned it a few times in these threads already... but for the love of all that is holy, try your mobile website/app in an actual phone where you have accessibility turned up for text and display.

I cannot tell you how many times I've experienced modals with buttons literally off screen and no navigation option in apps from multi-billion and trillion dollar tech companies. Almost as bad is gmail allowing text to scale so insanely large that it's equally unusable.