Hello HN!As apps grow increasingly complex, I started to question whether only feature-packed apps are truly helpful. That led to what I call the *Small App Project*—a philosophy of building small, focused tools that do just what you need, and nothing more.Money Keeper is one of the apps I created as part of the Small App Project. It’s a small expense tracker built for clarity and efficiency.---What it does:- Fixed Expenses. Easy to Grasp at a Glance.- Payday Calendar. Customize Your Start Day.- Monthly Summary. Expense Visualization.- Customizable Categories.- No Ads. No Data Collection.- Regular Updates Based on User Feedback.- Seamless Sync Across iPhone, iPad, and Mac.You can download Money Keeper here: https://apps.apple.com/app/id6514279917---[Tech] Mac CatalystMoney Keeper is built using a single codebase that runs across iPhone, iPad, and Mac—thanks to Apple's *Mac Catalyst* technology.Mac Catalyst is a framework provided by Apple that allows iPad apps to run on macOS with minimal changes. By leveraging this, I was able to bring Money Keeper to the Mac with much less overhead, both in terms of time and complexity.My biggest concern when launching a Mac Catalyst app was *stability*. Was it reliable enough for real users in production environments? I first tested the waters with my other app, Scheduler, which has now been running on the Mac for over six months. The result? It’s been solid. I gained enough confidence in Catalyst to use it again for Money Keeper.The second challenge was *feature limitations*. Mac Catalyst apps don’t have full access to AppKit or certain macOS-native capabilities. Thankfully, most of those gaps weren’t critical, and I found ways to either work around them or plan a native Mac alternative if ever needed.As a solo indie developer, time is everything. Mac Catalyst has been an incredibly helpful tool that enables me to build cross-platform apps efficiently. I’m especially excited about the improvements in macOS Sequoia (macOS 15), which further enhance support for iPad-style SwiftUI views on the Mac.If you're an iOS developer interested in expanding to macOS, I highly recommend giving Mac Catalyst a try.---I'm a solo indie developer. If you have any feedback or run into issues, feel free to leave a comment here or use the in-app “Send Feedback” button. I'll do my best to respond.---Small App ProjectThe Small App Project is a personal mission to create tools that are intentionally simple—focused only on what truly matters.I began to wonder: Are only complex, feature-rich apps truly valuable? Could a simpler, more focused tool actually be more helpful?Money Keeper was born from this line of thinking. It’s designed to be straightforward and efficient, offering just the core features needed to manage personal expenses—nothing more, nothing less.I believe small apps can provide big value. If you prefer clarity over complexity, I hope this app is useful to you.You can check it out here: https://apps.apple.com/app/id6514279917Comments URL: https://news.ycombinator.com/item?id=44334134Points: 1# Comments: 0