iPhone

HEIC to JPG on iPhone (Safari)

You do not need a separate App Store converter. Safari on the same iPhone that shot the still can decode many HEIC files natively. Open https://heic-local.vercel.app in Safari — not inside Instagram’s in-app browser, not inside Gmail’s preview, not inside a MDM “secure browser” that strips downloads. Those shells often block the blob download or kill WASM. If you arrived from a chat preview, tap Open in Safari, then convert.

Photos picker

The picker should offer the camera roll. A HEIC still from Camera, Portrait, or a screenshot saved as HEIC is in scope. Live Photo: you get the key still, not the 3-second MOV. Burst: export the frame you care about from Photos first; a multi-image HEIF may fail as one tile. ProRAW saved beside HEIC is a different file — this page does not develop RAW. A video you renamed to .heic is refused on purpose.

Stay in the tab

iOS Safari discards heavy pages that sit in the background. Convert, wait for the thumbnail, then Download. The share sheet can save to Files, Mail, or WhatsApp. If the sheet never appears, check that From-the-tool errors are not sitting under the button (oversize file, not a still). Tap Convert again; a popup blocker or an IT profile can swallow the first blob. Keep the phone unlocked and Safari in front until the sheet appears. Pocketing the phone mid-WASM is how a 12 MP still dies.

Low Power Mode does not always kill WASM, but a locked screen often does. If Convert freezes after you pocket the phone, unlock, keep Safari in front, and run that one file again. A batch of 50 is the documented ceiling so a tab does not die; on a 3 GB iPhone treat 10 as a practical batch. Concurrency on iPhone is 1 — one frame at a time.

Share sheet is the save button

Safari’s download sheet is the save button. There is no “email me the JPEG” on this origin, because that would be an upload. If Mail is your next step, attach the file you just saved, not the HEIC in Photos, unless the recipient is also on iOS and you already know they can open it. Desktop WhatsApp is the usual reason people convert on the phone before they sit at a PC. Longer notes: HEIC in WhatsApp.

Huge 48 MP stills starve an old phone. Soft guard is about 40 MB per file. Compress is not this product — if you already have a JPEG, Crush lives on another hostname. localStorage on iPhone is this Safari profile, not iCloud of every device. We do not push the JPEG into Files.app for you; that is the share sheet after download.

In-app browsers

In-app browsers (Telegram, Slack, Facebook, Instagram, Gmail) inherit WebKit with download quirks. If Choose photos works but Download does not, copy the URL into Safari and repeat. We cannot patch those shells. Chrome on iOS is WebKit underneath, so behaviour is close to Safari; still prefer Safari when a download fails once. A work MDM profile that blocks blob URLs will fail every converter in a tab, not only this one.

Do not email the original

Do not email the original HEIC to ultaultimatum@gmail.com for “us to convert.” That defeats the tool. The contact page explains the triad we actually need: page URL, browser, what failed — never the picture.

This page is not a tutorial for turning off HEIC in Camera. “Most Compatible” only changes future shots and uses more space. The roll you already have still needs a decode. That is this tab. Step-by-step that is not Safari-specific: how to convert without uploading. Short answers: FAQ.

If Files.app shows the JPEG but Photos does not, that is expected: Photos is a camera library, Files is a document tree. Save to Files when a print shop asked for a file, not a camera roll screenshot. A screenshot of the converted preview is a new JPEG of the screen, not the decoded frame — do not send that to a printer and call it the export. Native createImageBitmap on current iOS often finishes before you notice a spinner. The WASM path is the same tab on older builds; it is slower, still local, still not an upload.