Hopply - An App I Built for Managing My Aircraft
TLDR
- Built a mobile app called Hopply for managing aircraft maintenance, squawks, and inspection dues
- Runs on both Android and iOS
- Still a work in progress, but I’ve been using it for my Sling build
Since this is not an essential part of my airplane build, I will only count 10 minutes for the time writing this blog. But in reality I probably spent 200-300 hours on this.
Why I Built It
As I get closer to finishing the Sling and start thinking about what happens after first flight, maintenance tracking becomes a real concern. There’s ADs, SBs, 100-hr inspections, annuals, and whatever squawks come up day to day. I looked at existing apps and they were either too simple (just a spreadsheet) or too expensive and complex.
I also had been wanting to try building something in Kotlin Multiplatform for a while, where you share most of the code between Android and iOS. So I decided to just build what I needed.
What It Does
Fleet Dashboard
The home screen shows a list of aircraft. For me it’s just the one Sling, but the app is designed to handle multiple aircraft so it could be useful for someone who owns a small fleet.
Aircraft Overview
Tapping into an aircraft opens a tabbed view. There are four tabs: Overview, Squawks, Tasks, and Logs.
Squawks
This is where I log issues I find during inspection or flight. Each squawk has a summary, priority (Low / Medium / High / AOG), and description. In edit mode, you can also link a squawk to a maintenance log entry once the issue has been addressed. That way you have a clear paper trail from “I found this problem” to “here is the work that fixed it.”
Maintenance Tasks
This tab shows all the inspection compliance items for the aircraft - ADs, SBs, and routine tasks like 100-hr and annual. Each task has a due status that gets computed automatically: Overdue, Due Soon, or OK. The list is sorted by urgency so the things that need attention bubble up to the top.
Maintenance Logs
Log entries for any work done on the aircraft. Each log has the date, description of work, and can be linked back to a squawk it resolves. This is basically a digital version of the maintenance logbook.
A Few Technical Details
The app is built with Kotlin Multiplatform, sharing all the logic and UI between Android and iOS. That’s been an interesting experience - the tooling has improved a lot over the past couple of years and it mostly just works.
Data is stored locally on the device first and syncs to Firebase in the background. I chose to go with a local-first approach to keep people’s data as private as possible. The backup & sync brings the convenience of 21st century so you will never worry about losing data.
Current State
It’s still a work in progress. I’m using it for my own Sling and adding features as I go. It’s not publicly available yet and I haven’t decided if or how I’d release it. For now it’s solving my own problem, which is good enough. There are are few big areas of improvements I still need to do:
- Importing from paper logs (via camera)
- Exporting to PDF
- Proactive notification/email for approaching dues
- AI diagnostics on squawks/inspection tasks
- etc
If there is any interest for this app I might consider publishing it on Google and Apple stores. You can express your interest in this form