i know what you mean about things looking small when viewed on a mobile Jo

i sometimes thing i need some binoculars to see mine
but no, the gallery button is still there, the mobile pages are different to the desktop ones, which i think is down the the size limits of phones,
its just hidden away from view most of the time,
if you look at the pics below, in the first one you can see three horizontal bars (highlighted inside a red circle)
if you tap on that, a menu appears which contains the gallery button,
among other things, so tapping on the gallery bit takes you to the gallery as normal
my phone is an old windows one, but i would imagine its much the same on android or iphones ?