TapSum

TapSum is a private, offline calculator for quickly totaling custom named numbers (sets). Designed for market stalls, events, and anyone who needs fast, repeatable totals without storing, accounts or cloud sync.

Key features

- Local-only storage: all data remains on your device unless you export it. No login, no cloud sync.
- Custom sets: group related numbers (products, items, fares) into named sets for fast access.
- Calculator screen: tap items to add, long-press to subtract, see counts and running total.
- Quick-change tool: enter given amount and compute change; quick-add buttons increment the entered amount.
- QR export / import: share or backup entire library or single sets via QR codes. Import mode: merge or replace.
- Offline-friendly: works fully without network access.
- Lightweight UI: dark/light themes, device-language support

Privacy & data
TapSum stores data locally in your device storage (no calculation history). Nothing is uploaded or shared. To move or back up data, use the QR export feature or copy the exported payload manually.

Who it’s for?

Market sellers, food trucks, event staff, small retailers.
Anyone needing a small, private tool to total repeated items or prices quickly.


Quick start

Create a set (e.g., “Coffee Stand”).
Add named numbers (e.g., “Latte — 3.50”).
Open calculator and tap items to build totals.
Use QR export to share sets or back them up.


Questions or feedback

If something doesn’t work as expected or you want an improvement, use the app contact option to report issues or request features.