Guides & Tutorials
Comprehensive, privacy-first guides on image formats, AI PDF editing, store asset compliance, and developer utilities — all processing 100% locally in your browser.
What Is a HEIC File?
HEIC is the high-efficiency image format iPhones use by default. Learn what a .heic file is, why Apple uses it, how to open it on any device, and how to convert it.
HEIC vs JPG vs PNG
A clear comparison of HEIC, JPG and PNG — file size, quality, transparency and compatibility — so you know which image format to use and when to convert.
How to Edit PDF Text & Sign Documents Privately
Learn how to edit existing text inside PDF documents, replace names and dates, add digital signatures, and rotate pages without uploading sensitive files to external servers.
App Store & Google Play Screenshot & Asset Specs
Complete 2026 checklist of required Apple App Store and Google Play Store screenshot dimensions, app icon specs, feature graphic sizes, and device mockup recommendations.
How to Compress a PDF Without Uploading It
Most online PDF compressors upload your file to a server. Here's how to reduce PDF file size entirely in your browser — free, private, and with no uploads.
How to Compress JPG, PNG & WebP Images
Master image optimization. Learn the difference between lossy and lossless compression, target file sizes, and how to batch shrink images directly in your browser.
Developer Utilities: JSON, Base64 & QR Code Guide
Essential guide for developers. How to format and minify JSON payloads, encode URL-safe Base64 strings, and generate high-resolution QR codes locally.