iPhone photos of paper
An iPhone shoots HEIC by default, and a large share of those photos are not holiday pictures but paperwork: a receipt held over a table, a whiteboard at the end of a meeting, a signed delivery note, a page of a textbook. Sooner or later the expense system, the landlord or the university portal asks for a PDF and does not know what to do with a .heic. This converter takes one or more HEIC photos and makes a single PDF from them, entirely on your device.
Two stages: decode, then lay out
HEIC is not something browsers decode on their own, so the tool uses heic2any, a WebAssembly build of libheif, to turn each file into a PNG in memory. That step is the slow part: a 12 megapixel HEIC typically takes one to three seconds on a recent laptop and noticeably longer on an older phone, and the decoder is loaded on first use. The decoded image is then drawn onto a canvas, encoded as JPEG at quality 92 and placed on a page whose size matches its pixel dimensions. Pages are added in the order the files were dropped and the finished document downloads as images.pdf.
What you gain and what you lose
You gain a document that opens everywhere. You lose a few things that were in the HEIC. The wide Display P3 colour that iPhones capture is converted to standard sRGB on the way through the canvas, which makes saturated reds and greens slightly less vivid, though on a receipt nobody will notice. Depth maps, Live Photo motion and any HDR gain map are discarded; only the main still image is used. EXIF metadata, including GPS coordinates, is not carried into the PDF. For a document going to a third party that is generally a benefit, and you can inspect what the original contained with the EXIF viewer before converting.
Orientation is handled during decoding, so photos taken in portrait come out upright. If a page still appears sideways, the phone recorded it that way and the crop and rotate tool fixes it before you combine.
A worked example: an expense report
Six receipts photographed at 4032 by 3024, each around 1.8 MB as HEIC. After decoding and JPEG encoding at 92, each page typically weighs 1.5 to 2.5 MB, giving a PDF of roughly 9 to 15 MB. That is larger than the HEIC originals, because HEVC compression is more efficient than JPEG, and it may exceed an email or portal limit. Shrink the photos first with the compress and resize tool, limiting width to about 1600 pixels, and the same six pages usually come in around 1.5 to 3 MB with receipts still perfectly legible. Figures are typical, not guaranteed.
Good habits for document photos
Fill the frame with the paper, avoid your own shadow, and shoot every page in the same orientation so the reader does not have to rotate. Crop each page tightly before combining. Add files in the order the pages should appear, because the tool preserves your order and does not sort.
Limits
Decoding is memory intensive, so the browser may pause for a moment per file, and a batch of thirty full resolution HEICs can exhaust a phone. The PDF contains images only, with no searchable text. Multi-image HEIC containers such as bursts contribute their primary image only. Nothing is uploaded at any point, and for background on the format itself see what is HEIC.