Filter Studio vs CanvasPrism

FilterStudio is a professional, on-device photo editor engineered for speed, control and privacy. Built on Apple Core Image and PencilKit, it delivers studio-grade output without a server round trip and without a single subscription prompt. ENGINE • 15 hand-tuned filters mapped to native CIFilter primitives — Mono, Noir, Fade, Chrome, Process, Transfer, Instant, Sepia, Vivid, Dramatic, Silvertone, Posterize, Bloom, Vignette, Original. • Real-time GPU pipeline — every slider rebuilds the preview at native resolution. • Lossless export — output written back to Photos at the full input pixel size, no recompression artifacts beyond standard PNG/JPEG. ADJUSTMENTS • Brightness — linear exposure offset. • Contrast — perceptual contrast curve. • Saturation — chroma scaling, clamped against banding. • Live preview, no commit step. LAYER SYSTEM • Text layer — UTF-8, dynamic font sizing, color and bold control, free positioning. • Sticker layer — vector-style emoji and shapes, scale and rotate. • Drawing layer — Apple Pencil first, finger fallback, multi-color. • Layers composited at export time, original photo never overwritten in place. WORKFLOW 1. Pick a photo via the system PhotosUI picker. 2. Apply filter, adjust, add text/stickers, doodle. 3. Crop and rotate if needed. 4. Tap Save — written to Photos with library write authorization only. PRIVACY & SECURITY • Strict on-device processing. No analytics, no telemetry, no third-party SDKs. • Photos library access is request-once, write-only by default. • No user account, no email collection, no IDFA usage. LOCALIZATION English and Simplified Chinese, switchable from in-app settings. REQUIREMENTS iOS 17.0 or later. iPhone only. PRICING Free. No tier, no consumable, no in-app purchase. FilterStudio is for users who want professional control without subscription friction. Install once, edit forever.

CanvasPrism is a fully offline, private whiteboard for iPhone and iPad. Everything you create is stored right on your device. There's no account, no sign-up, and no internet connection required to draw, sketch, or edit. Your ideas stay yours. Open a blank board and start working in seconds. • Infinite canvas for freehand sketching with shapes, arrows, lines, and text • Build flowcharts, mind maps, and wireframes using smart shape connectors • Ready-made component libraries and templates to start fast • Apple Pencil support on iPad with native double-tap and squeeze gestures for a natural, hand-drawn feel • Customize with 100+ bundled fonts, color themes, and background styles • Set dark or light appearance per board for full control over every canvas • Export to PNG, PDF, or SVG with an optional transparent background • Open and import .excalidraw and .excalidrawlib files • Share your work straight to Photos or Files Want your boards on every device? Turn on optional iCloud sync to keep your iPhone and iPad in step. Sync is conflict-safe: if a board is edited in two places at once, CanvasPrism keeps an automatic copy so nothing is ever lost. Leave it off and CanvasPrism stays completely offline and on-device. CanvasPrism is built on the open-source Excalidraw engine, running natively in the app for a fast, responsive drawing experience. CanvasPrism is is completely free with no ads, no tracking and no account. Just a clean, capable whiteboard that's ready whenever inspiration strikes. Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/