DEV Community: Aarush Prakash

My experiences

Aarush Prakash — Thu, 19 Feb 2026 00:30:46 +0000

I Built a #1 App Store Developer Tool in Pure SwiftUI — Here's What I Learned

Aarush Prakash ・ Feb 19

#swift #webdev #development #productivity

I Built a #1 App Store Developer Tool in Pure SwiftUI — Here's What I Learned

Aarush Prakash — Thu, 19 Feb 2026 00:12:19 +0000

I got tired of jumping between browser tabs every time I needed
to format JSON, convert a color, test regex, or hash a string.
So I spent 6 months building a fix.

The result: Devly — a native macOS menu bar app with 50+
developer utilities. It just hit #1 in Developer Tools on the
App Store.

The Problem I Was Solving

Every developer knows the pain. You need to:

Quickly format some JSON
Convert a hex color to RGB
Test a regex pattern
Decode a Base64 string
Generate a UUID

So you open a browser tab. Then another. Then another.
Context switching kills your flow.

What I Built

Devly sits in your macOS menu bar. One click gets you instant
access to 50+ tools:

Encoding: Base64, URL, HTML, JWT, Unicode, Morse, ROT13
Hashing: MD5, SHA-256/384/512, HMAC, bcrypt, UUID generator
Formats: JSON, YAML, XML, CSV, SQL, TOML
Web Dev: Color converter, CSS/JS minifier, Markdown preview
Text: Regex tester, diff tool, case converter, timestamp converter

The Technical Challenges

1. Apple's App Sandbox

The biggest hurdle was getting all 50+ tools to work within
Apple's strict sandbox rules. Every tool that processes data
locally has to comply — retrofitting this late in development
was painful. Lesson: plan for sandbox compliance from day one.

2. Keeping the UI Truly Native

SwiftUI on macOS is still maturing. Getting the menu bar
popover to feel truly native — proper sizing, smooth
transitions, correct macOS conventions — required constant
referencing of Apple's Human Interface Guidelines.

3. Managing State Across 50+ Tools

I used a ToolProtocol pattern that each tool conforms to:

protocol ToolProtocol {
    var id: String { get }
    var name: String { get }
    var category: ToolCategory { get }
    func process(input: String) -> String
}

This kept everything consistent and made adding new tools
much faster.

4. Discoverability

With 50+ tools, finding the right one fast became a UX problem.
I built a custom SearchService that indexes tools by name,
category, and keywords.

What I'd Do Differently

Plan for sandbox compliance from day one
Build the ToolProtocol pattern earlier
Study the macOS HIG before writing any UI code
Test SwiftUI popovers on macOS early — they're quirky

The Result

6 months of nights and weekends. #1 in Developer Tools on
the App Store. Pure SwiftUI, fully
sandboxed, $4.99 one-time.

App Store

Website
All 50+ tools

What challenges have you hit building native macOS apps
in SwiftUI? Would love to hear in the comments!

I Built MindHalo — a Local AI Study Tool for macOS

Aarush Prakash — Wed, 19 Nov 2025 22:21:01 +0000

I Built MindHalo — a Local AI Study Tool for macOS

Hi everyone! I’ve been working on a macOS study tool called MindHalo, and I wanted to share it here since a lot of developers and students might find this interesting.

MindHalo is a lightweight AI-powered study assistant designed to help students turn their notes into clean study guides, generate flashcards, and ask questions through an interactive on-device tutor. Everything runs locally on Apple Silicon using Apple’s Foundation Models API — no cloud, no accounts, no stored data.

Why I Built It

Most study tools today are:

Cloud-based
Slow
Require accounts
Send data to external servers

I wanted something that:

Works offline
Respects privacy
Runs fast on M-series chips
Helps students understand tough topics quickly

So I built MindHalo as a native macOS app using SwiftUI and Foundation Models.

Key Features

Convert Notes into Study Guides

Paste or import your notes, and MindHalo generates a structured, easy-to-review study guide with:

Key points
Summaries
Explanations
Terms and definitions
Suggested areas to focus on

It uses on-device models, so your text never leaves your Mac.

Flashcard Generator

MindHalo automatically detects important concepts and converts them into flashcards you can save and review later.

Interactive AI Tutor

Ask follow-up questions, get explanations, or break down complex topics.

Because everything runs locally:

Responses are instant
Your data stays private
There's no rate limiting

Perfect for studying or clarifying homework problems.

Built with SwiftUI + Apple Foundation Models

MindHalo is written in SwiftUI with a clean, native macOS interface.

It uses Apple’s Foundation Models API to run all intelligence on-device, keeping the experience fast and private.

The activation system is hardware-bound (to prevent abuse), but during the beta, the entire app is fully free.

Free Lifetime License (Beta Only)

While MindHalo is in beta, anyone can generate a free lifetime license key, even if the app becomes paid later.

You can get the license key on the same page where you download the app:

Download & Get Your Free License:

https://mindhalo.techfixpro.net/

This offer only applies during the beta period, so feel free to grab one now.

Version Highlights

v1.0.3 — Added support for generating study guides from notes
v1.0.2 — Bug fixes and stability improvements
v1.0.1 — Added saving for flashcards, study guides, and conversations
v1.0.0 — Initial release

Why I’m Sharing This

I’m actively improving MindHalo and would love feedback from other developers, students, or anyone interested in local AI on macOS.

Thanks for reading — happy to answer questions or chat about the implementation!