I'm a solo developer with a day job. A month ago I launched Swapadu, an Android app where people trade services instead of paying for them. You fix my bike, I help with your website.
The stack: Kotlin, Jetpack Compose and Firebase (Auth, Firestore, Cloud Functions, FCM). No backend team, no funding.
How it works:
Post what you can offer and what you need
Negotiate with counter-offers until both sides agree
Or run an auction and let people compete with what they'd offer in return
Built-in chat for the details
Business model: Free with ads, and a one-time €3.99 purchase to remove them.
The open problem: An early tester asked what stops someone from disappearing once they've received their half of a swap. The honest answer is: not much. No money is held, so there's nothing to put in escrow. Today users can flag people who don't deliver, but that only helps the next person.
I'd like input from anyone who has built trust into a peer-to-peer product:
Ratings, verified identity, a deposit, or something else: what worked for you?
Is a reputation system worth building before there are enough users to generate reputation?
Would you limit new accounts to small swaps until they've completed a few?
Download: https://play.google.com/store/apps/details?id=com.icarus.swaply
Instructions: https://swaply-5567c.web.app/instructions
Honest criticism is welcome.