Jonas Notes

SWAP

5 min read

Questions

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Teachings

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TODO

Potential project: personal spending ingestion and analytics

Problem: most purchases happen through online payments and Apple Pay across multiple banks and apps. The current monthly flow of exporting transaction PDFs, transforming them into a personal format, and then storing/analyzing them is too manual.

Goal: build a self-hosted spending pipeline with:

  • iPhone-side or middleware ingestion whenever a payment happens.
  • Best-effort extraction of amount, merchant, timestamp, payment method/card, bank/app source, and raw evidence.
  • A central online database hosted by me.
  • A frontend with a comprehensive view of spending, trends, categories, reimbursements, and card reward limits.

Initial research finding: a normal iPhone app probably cannot read all notifications from other apps. iOS does not expose an Android-style notification listener API to App Store apps. Apple notification APIs are for an app’s own notifications/extensions, not arbitrary banking app notifications. There is, however, an Apple Shortcuts Wallet Transaction trigger that can run an automation when a selected Wallet card/pass is tapped. This may cover some Apple Pay tap transactions, but not every online payment, PayNow, bank-app notification, Apple Watch payment, recurring payment, or delayed card posting.

Practical starting direction: use email alert parsing for near-real-time capture, monthly PDF/CSV statement parsing for completeness/reconciliation, and Apple Pay Shortcuts as an optional convenience layer. Treat Wallet/Shortcuts data as helpful but not the source of truth.

Sources to revisit:

Potential ingestion paths to test:

  • Email alert parsing through Gmail/IMAP → parse bank/card alerts → POST normalized transactions to my backend.
  • Bank statement/PDF/CSV ingestion as monthly reconciliation and source of truth, but make parsing and reconciliation much less manual.
  • Shortcuts Wallet Transaction automation → extract transaction/card/merchant/amount/name → POST JSON to my backend. Useful for Apple Pay taps, but not authoritative.
  • Shortcuts SMS/email automations for bank alerts where the message body is available and user-configured.
  • Bank/open-banking APIs if a consumer-accessible route exists; Singapore bank APIs seem mostly partner/corporate-facing, while SGFinDex may be useful for financial snapshots but probably not easy transaction-level hobby ingestion.
  • Commercial aggregators like Salt Edge if Singapore coverage is good enough, but check cost/privacy/coverage before relying on this.
  • Android notification listener or a secondary Android device as an experimental workaround, if iOS coverage is too limited.
  • Mac notification mirroring/OCR/screenshot approaches only as a last-resort hack.

MVP question: can I reliably capture enough transactions without reading arbitrary iOS notifications? Start with email alert parsing plus statement reconciliation; add Apple Pay Shortcuts ingestion if it gives useful extra timeliness.

Good-to-have once ingestion works:

  • Group payments/reimbursements: track cases where I pay first for food or shared expenses, then friends PayNow me later. Reconcile repayments against original group expenses and estimate my actual personal spend.
  • Missing repayment detection: infer who has not paid back and how much remains outstanding.
  • MCC tracking: show MCC per transaction where available or infer/check merchant MCC where possible. This matters for UOB Preferred Platinum Visa 9x UNI$ eligibility and UOB Lady’s Card travel-category optimization. Normal SG bank exports may not expose raw MCC, so this may need merchant lookup, manual correction, or issuer/aggregator data.
  • Card reward limits: track spending against UOB monthly caps and category caps, especially PPV online/mobile-contactless buckets and Lady’s Card travel category.

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