Stop reading syntax. Start reading documents.
hYYa ink opens the files developers, students and academics work with every day, and turns them into readable, editable documents instead of walls of raw text.
ONE APP, MANY FORMATS
• Markdown — rendered live, with a formatting toolbar
• JSON, YAML, TOML, XML — collapsible trees instead of nested brackets
• CSV and TSV — a real table you can read across
• Mermaid and Graphviz — diagrams drawn on your device, fully offline
• LaTeX — maths typeset properly
• Jupyter notebooks — prose, code and text output, cleanly laid out
• AsciiDoc, Org-mode, diff, logs — readable at last
• PDF — a first-class document, not an afterthought
EDIT THE SOURCE, WATCH IT UPDATE
Switch between the document and its source in one tap. Turn your phone sideways, or use a tablet, and Split view shows both at once. Markdown gets a toolbar for headings, bold, italics, lists, quotes, code and links. Saving writes back to the file you opened.
PDF — READ, SEARCH, FILL IN, SIGN
Open any PDF as a real document. Select and copy its text. Search it, with a running match count. Browse the pages as thumbnails and jump straight to the one you want. Is the file password-protected? hYYa ink asks for the password and opens it.
To add text, tap the exact spot on the page and type, then drag the text into place. Draw your signature by hand, then place, resize and turn it. Draw freehand on a pad and place the drawing on the page; with a stylus, pressure sets each stroke's weight. Drag across a line of text to highlight, underline or strike it through. Undo removes the last thing you added.
Make a scanned PDF searchable. Text recognition runs on your device, and your pages never leave it. It reads Latin script and Arabic.
You can also reorganise pages, protect a PDF with a password, compress it or add a watermark. Redaction removes the words from the page, rather than just covering them up.
Each of these, like making a PDF searchable, writes a NEW file, and the PDF you opened is never changed. You can also compare two PDFs to see which pages differ.
BRING YOUR OWN AI
Use your own key with an AI service: OpenRouter, OpenAI, Groq, Together AI, or another service that works the same way. The AI actions work on every format except PDF: explain, summarize, reformat or fix errors in a document, or write Mermaid code for a diagram of it. Your key is encrypted on the device. Only the open document's text is sent, and only when you run an action.
PRIVATE BY DESIGN
No accounts. No ads. Every format renders offline on your device, and your documents stay there unless you run an AI action. Google's text recognition sends Google its own diagnostics — never your documents.
FREE TO READ, PRO TO EDIT
Reading every format is free forever — and so are Export to PDF and Print. On PDFs, searching the text, copying it and browsing the pages are free too.
A 7-day trial unlocks everything. After that, a single one-time purchase unlocks editing, the PDF tools and AI permanently. No subscription.
From hYYa — more than apps. Companions you can trust.
PDF, Markdown & code editor. Read and edit JSON, CSV, YAML, LaTeX and more.