Reading a photo on the device that took it.
Both phone platforms will show you some of what a photo carries. Neither shows you all of it.
On an iPhone
Open the photo in Photos and swipe up, or tap the info button. You get the camera and lens, the exposure settings, the file size and dimensions, and — if the photo has coordinates — a small map with the place name. The same panel is where you can adjust or remove the location for that photo in your library, which is worth knowing: it changes what the library holds, and it is not the same as changing a copy you are about to send.
On Android
In Google Photos, swipe up on the photo or tap the info button for a similar panel: date, camera, exposure and a map when location is present. What you see beyond that depends on the manufacturer, because gallery apps differ between phone makers and some show considerably less. A file manager will usually show only the size and the date.
What the built-in panels leave out
Both are curated views of a handful of fields. Neither shows you the IPTC caption, the XMP block an editor wrote, the colour profile, the vendor's private notes, or the thumbnail embedded inside the metadata. If your question is what a file discloses rather than what settings were used, that gap is the important part.
Reading the raw tags on the phone itself
A browser is enough. This workspace parses the file with the browser's own capabilities, so it works from a phone the same way it works from a desktop, and the photo is never uploaded — which matters more on a phone, where the file you are curious about is usually a personal one.
Open a photo from your phone
Choose a photo from your camera roll and you get the full tag table rather than a summary panel. Nothing is sent anywhere.