Technology

How PDF JustFit Works

How PDF JustFit processes documents on-device — and why that matters for both privacy and speed.

Short answer: PDF JustFit runs compression, conversion, OCR and AI on-device. Its AI document chat uses open models including Gemma 3 and Qwen3, downloaded once, after which AI chat works offline. The network is used to download model weights, not to upload documents.

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On-Device AI for PDF Documents

How PDF JustFit runs AI document chat locally with open models including Gemma 3 and Qwen3, and works offline after the model is downloaded.

OCR and Document Indexing

How OCR turns scanned page images into text, and why that text layer is what makes search and AI document chat possible.

How PDF Compression Works

What makes a PDF large, how compression reduces it, and how a two-stage solver reaches an exact target size.

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Last verified: October 3, 2026

Keep your documents light, organized and private

PDF JustFit: Compress, AI Chat is available on the App Store for $9.99. Requires iOS/iPadOS 26.5 or later.

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