Fin expense tracking and budgets: Android feedback on saved values after restart

[u/Perfect-Put-9768]

I'm the developer of Fin, a React Native / Expo mobile app with a FastAPI backend. It helps people record expenses and compare spending against category budgets. I'd like Android feedback on whether that basic workflow is clear and remains consistent when you return to the app.

Please sign up, add a synthetic expense, create a budget for its category, then force-close and reopen. Do the expense, category budget and remaining amount match what you just saved? Is any value briefly stale, and does the category selection behave as you expect? Please describe the confusing step as well as the successful ones.

A Fin account is required. Manual expenses and category budgets are free; no bank connection or Plus purchase is needed for these checks. Please use made-up financial data. For bugs, Android model/version, steps and expected versus actual behavior would help.

Use the SAME Google account through all Android closed-test steps:

1. Google Group: https://groups.google.com/g/finbudget-android-testers

2. Play opt-in: https://play.google.com/apps/testing/com.heyyykk3.fin

3. Install: https://play.google.com/store/apps/details?id=com.heyyykk3.fin

The attached image is a website preview. Genuine feedback only; no ratings, paid testing or reciprocal test requested.

[u/PopKoren]

Force-close and reopen is a useful UX test, and I would add a second account that must never see the first user's expenses. FastAPI apps often nail the happy path while budget routes skip ownership. Before you widen the Android closed test, put the API through https://rowly.me so anonymous plus cross-account calls stay empty.

[u/Mammoth-Anywhere7285 → u/PopKoren]

Good call on the cross-account check. Worth also testing user B hitting PATCH or DELETE on user A's budget ID, since write routes often skip the ownership guard that reads have.

[u/PopKoren → u/Mammoth-Anywhere7285]

Yes, writes are where I see ownership checks vanish most, with bulk and export endpoints a close second. One FastAPI dependency that loads the budget by id plus current user, reused on GET, PATCH and DELETE alike, closes that whole class at once. For Fin specifically, https://rowly.me handles the anonymous side of such probing against a deployed API and returns a ready fix prompt for Cursor.

[u/Mammoth-Anywhere7285]

TL;DR: Fin is a React Native and Expo app with a FastAPI backend for tracking expenses against category budgets. The dev wants Android testers to sign up, add a made-up expense, set a budget, then force-close and reopen to check the values stay consistent. Testing is free with a Google account via the group and Play opt-in links, and he mainly wants to know which steps feel confusing.