You searched this because a photo is gone and the results are full of apps promising to bring it back with no backup. Here is what those $40 apps will not say plainly.
Recovery is only ever copying a photo that still exists somewhere. If a surviving copy exists in a trash folder, a cached thumbnail, or a backup, it comes back, often for free. If no copy exists anywhere, it is gone, and no software changes that on a modern phone. Let's find out which case you're in.
Why "deep scan the phone's memory" no longer works: modern iPhones and Android phones encrypt every file. When you delete a photo, the key for that file is thrown away, so the leftover bytes are unreadable noise, and the storage physically wipes those blocks within minutes. Tools that claim to "scan deleted storage" are describing a decade-old world. Today they really just read your trash and backups.
Work through these. Most people's photo is in one of them
1. Recently Deleted, the 30-day net
iPhone: Photos, Albums, scroll down to Recently Deleted. Android (Google Photos): Library, then Trash. Deleted photos wait here about 30 days and restore with a tap. Astonishingly often, this is the whole answer.
2. iCloud or Google Photos trash, the cloud copy
If your phone's trash is empty but you use cloud photos, check the cloud's own trash: iCloud at icloud.com, Photos, Recently Deleted (about 30 days). Google Photos Trash keeps backed-up items about 60 days. This is a separate net from the phone.
3. A computer backup, the case people forget they have
Ever plugged your iPhone into a Mac or PC and backed up? That backup contains every photo from that date, including ones you've since deleted. You don't need to restore it, which wipes your phone. You can read it directly.
Open an iPhone backup, free4. Cached thumbnails, a last-resort small copy
Even for photos deleted beyond every window, your iPhone often kept a small thumbnail in its cache. It is low resolution, not a real restore, but it is proof the photo existed and a small image of it. Our recovery tool carves these out of a backup automatically, in a clearly labeled "older deletions" section.
If none of those have it
Then the honest answer is that it is gone, and that is not a limitation you can pay your way past. We know that is not what the ads promised, but you'll save the $40 and the disappointment. The lesson worth taking: set up a backup now so the next scare has an answer. On iPhone, turn on iCloud Photos or back up to a computer. On Android, turn on Google Photos backup. See our backup guide, which covers photos and messages.
Android specifically
Android has no readable local backup like the iPhone's, so options 1 and 2 (Google Photos Trash plus a recycle-bin app) are the realistic ones. Details in our Android note.