App Dev
Mobile architecture with React Native and Expo, store asset production, performance tuning, and post-launch operations for indie developers shipping apps.
Keeping a wallpaper app's binary small: moving images out of the bundle
Wallpaper apps bloat every time you add images. Here is where I draw the line between bundled and remote assets, how I keep first paint fast with prefetching, and the format work that cut transfer size to a third — with real numbers.
expo start --offline Says 'forbidden'? Corporate Proxy (403) vs Dependency Validation
Two different failures make 'expo start --offline' or EXPO_OFFLINE=1 die with 'forbidden': an HTTP 403 from a corporate proxy, and Expo CLI validateDependenciesVersions guard. How to tell them apart, when to set HTTP_PROXY to route through the proxy, and when to go fully offline with pre-generated caches instead.
How I Localized My Play Store Screenshots into 16 Languages — Swapping PSD Text with Python and Standardizing on Noto Fonts
An implementation log of localizing an Android wallpaper app's store screenshots into 16 languages: swapping PSD text layers per language with Python, auto-shrinking overflow, and assigning the right font per script — with the actual code and a font cheat sheet.
Unifying Onboarding Across Six Wallpaper Apps: What One Month of First-Day Retention Showed Me
I folded the onboarding flows of six wallpaper apps scaffolded with Rork into a single config-driven component and watched first-day retention and push opt-in for a month. Here is an honest, operational note on what moved and what didn't.
Fixing the 'Signed With the Wrong Key' Error When Uploading a Rork App to Google Play
Your Rork app builds fine but Google Play rejects the upload with 'signed with the wrong key'? Here's how to tell which signing key is involved and the exact steps to fix it for each build setup.
Retuning AdMob Mediation Priorities: Notes From Trying to Lift My eCPM
A running log of how I manually revisited the network priorities in my AdMob mediation setup to lift eCPM on an indie wallpaper app, what changed compared to leaving it on auto-optimization, and what I noticed along the way.
Getting Users All the Way to 'Set as Wallpaper' on iOS — Save-to-Photos Permissions and Shortcuts
iOS apps cannot set the wallpaper directly. Here is how I handle add-only photo permissions, Live Photo saving, guiding users to Settings, and Shortcuts automation, with real numbers from running six wallpaper apps.
Killing Thumbnail Scroll Jank in an iOS Wallpaper App — Notes on ImageIO Downsampling
Lay out a lot of thumbnails and scrolling stutters while memory balloons. The culprit was full-size image decoding on the main thread. Here is how ImageIO downsampling and prefetching cut measured memory dramatically.
Two Weeks of Maintenance After v2.1.0 — Running Crashlytics Triage Through Claude in Chrome
Notes from operating Beautiful 4K/HDR Wallpapers v2.1.0 and Ukiyo-e Wallpapers v1.8.0 through phased rollout. Defensive RecyclerView copies, Glide desugaring, drawable-nodpi placement, and what I now hand off to Claude in Chrome every morning.
Three Weeks of Syncing Release Notes Across Six Wallpaper Apps
Notes from three weeks of writing What's New entries for six wallpaper apps in the same week, with the same tone, using Rork as the source of truth.
Adding Slideshow and Page Jump to My Android Wallpaper Apps
Implementation notes from adding slideshow, a page-jump slider, and an ad-free option to the Android editions of Beautiful 4K/HDR Wallpapers and Ukiyo-e Wallpapers.
Supporting iPhone Air and 17 Pro Max New Resolutions Across Six Apps in Parallel
How I added iPhone Air (420×912), 17 Pro (402×874), and 17 Pro Max (440×956) support across six apps in parallel — 29 ternary branches, a 6-app diff script, and a phased rollout that landed at zero resolution-related crashes in 14 days.
Bolting WidgetKit onto a Rork iOS App: Implementation Notes from Rolling It Out to Six Wallpaper Apps Simultaneously
A hands-on note on adding a WidgetKit Extension to a Rork-generated iOS app, with operational lessons from rolling out widgets to six wallpaper apps at once — App Group plumbing, Timeline Provider choices, memory ceilings, and ASO side effects.
Adding AppLovin MAX to a Rork-Generated iOS Project — A Field Note on Init Order, ATT Consent, and eCPM A/B Testing
A field note from an indie developer on layering AppLovin MAX on top of a Rork-generated iOS app: SDK initialization order, ATT and MAX consent flag sync, and a minimal A/B setup to compare eCPM against AdMob-only.
Slow Images in My Rork Wallpaper App: Switching to expo-image and What Actually Changed
A hands-on account of switching from React Native's default Image component to expo-image in a Rork-generated wallpaper app — with code examples, blur hash setup, and observable performance improvements.
What '16 Person-Days in 2 Hours' Actually Teaches About AI App Development
A widely-shared case study compressed 16 person-days of development into 2 hours. The key wasn't the AI — it was a design doc thorough enough that the AI never had to stop and think. Here's what that means for app development.
Designing Subscription Apps with Rork — From Revenue Model to App Store Approval
How to add a subscription revenue model to apps built with Rork — covering pricing design, StoreKit integration, and the specific issues that cause App Store rejections.
Native iOS Apps with Rork: SwiftUI to TestFlight
New iPhone projects in Rork are generated in Swift and SwiftUI, and Rork Pro carries them all the way to the App Store. How to tell an old Expo project from a new one, costs in credits, the skeleton prompt, device testing, when to drop into Xcode, and TestFlight submission.
Comparing the Five Leading AI App-Building Tools — Rork, Bolt, v0, Replit Agent, Cursor
'Build apps with AI' is a crowded claim. Here is a hands-on comparison of Rork, Bolt, v0, Replit Agent, and Cursor — what each one is for, where each one earns its price, and how they fit together.
Getting Started with No-Code AI App Development — The Three Decisions That Actually Determine Whether You Ship
Building an app is easier than ever. Shipping one is still hard for most beginners. The fix isn't choosing the right tool — it's three design decisions you should make before touching the builder.
Building a Wallpaper App with Rork and Getting It on the App Store — A Full Account
A complete record of building a wallpaper app with Rork from zero to the App Store — the iOS wallpaper API limitation, WebP optimization, and how to structure revenue without breaking the experience.
Gemma 4 for App Development: On-Device AI on the Cutting Edge
Learn how to integrate Google's Gemma 4 E2B and E4B models into iOS and Android apps for on-device AI. Covers privacy, offline capability, low latency, and practical code for real app use cases.
Fix Rork Android Build Errors: Gradle & SDK Troubleshooting Guide
Struggling with Android build errors in your Rork app? This guide covers the most common Gradle errors, SDK version mismatches, and memory issues — with step-by-step solutions for each.
Build an AI Personal Trainer App With Rork: Workouts, Nutrition, and Daily Coaching
A step-by-step guide to building an AI-powered fitness coaching app with Rork. Covers workout logging, food photo analysis, AI daily advice, progress charts, and push notifications — all without writing code.
Rork App AdMob Ads Not Showing — How to Fix Missing Ads and Revenue Issues
Fix AdMob ads not displaying in your Rork app and troubleshoot revenue not reflecting. Covers test ID mistakes, app-ads.txt setup, policy violations, and step-by-step solutions.
Rork App Monetization Complete Strategy: Building Revenue from Zero with AdMob, Subscriptions, and In-App Purchases
A complete guide to monetizing apps built with Rork. Covers AdMob ad design, subscription setup, and in-app purchases — with practical insights from an indie developer generating over ¥1M/month. Full content, free.
Rork Max × Foldable iPhone 2026 — App Design Strategy for the Folding Screen Era
Multiple supply chain sources indicate a foldable iPhone is coming in late 2026. Here's how to use Rork Max and SwiftUI adaptive layouts to get your app ready now — before the device ships.
Beta Testing Your Rork App with TestFlight: from Internal Testers to Public Launch
A practical walkthrough for shipping a Rork or Rork Max app to TestFlight, covering both the EAS Submit route and the Xcode Organizer route. Includes export compliance, internal (100) and external (10,000) tester limits, and the 90-day build expiry that quietly breaks long betas.
The Complete App Store Visual Strategy — Icons, Screenshots, and Preview Videos
Comprehensive guide to all app store visual assets: icons, screenshots, feature graphics, and preview videos. Master ASO strategy, A/B testing, and the complete workflow from design to store launch.
Figma vs Stitch vs Canva — The Ultimate App Screenshot Tool Comparison
Comprehensive comparison of Figma, Stitch, and Canva for app screenshot creation. Evaluate ease of use, templates, customization, device frames, speed, and output quality to choose your perfect tool.
Creating App Store Screenshots with Figma
A Figma workflow for App Store and Google Play screenshots, rebuilt around the current official specs (checked October 2026): which sizes to make, how to leave room for long translations, and how to export and re-check before submitting.
Production AI Companion Apps: Streaming, Voice & Monetization
Build a production-grade AI companion with streaming responses, voice I/O, mood tracking, offline support, and subscription monetization. App Store submission guidelines included.