On the mobile site, mapframes display zoomed out to show the whole world if any sort of data (GEOJSON, OSM data or Commons .map pages) are displayed on top of the basemap; the page must be loaded with the relevant section collapsed (collapsing all sections is the default behaviour on phones).
Visit this example page on a phone. The maps above the section break work correctly. Most of the ones below the break do not (the only ones that do are the one where no data is being drawn on top of the base map and the one where the zoom is manually specified).
Note that all maps display correctly if the page is reloaded with the section expanded (because the section remains expanded when the page is reloaded).
QA Results - Prod