---
title: "PopUp ‑ Sell by Weight Shopify App Profile"
description: "Shopify POS can't sell by weight. So like most market vendors, I ran two systems — Square for in-person, Shopify for everything else. Two catalogs, two logins, manual reconciliation every tax quarter. I built PopUp because I needed it. PopUp adds weight-based selling to Shopify POS. Mix weight and flat-price items in the same cart. On-device catalog, no Shopify inventory needed, works offline. Pause between seasons, no data lost."
canonical_url: "https://shoplist.co/shopify-apps/popup-sell-by-weight"
markdown_url: "https://shoplist.co/shopify-apps/popup-sell-by-weight.md"
last_updated: "2026-10-13"
entity_type: "shopify_app"
slug: "popup-sell-by-weight"
source: "public Shopify app profile allowlist"
---

# PopUp ‑ Sell by Weight Shopify App Profile

> Shopify POS can't sell by weight. So like most market vendors, I ran two systems — Square for in-person, Shopify for everything else. Two catalogs, two logins, manual reconciliation every tax quarter. I built PopUp because I needed it. PopUp adds weight-based selling to Shopify POS. Mix weight and flat-price items in the same cart. On-device catalog, no Shopify inventory needed, works offline. Pause between seasons, no data lost.

## Quick answer
PopUp ‑ Sell by Weight has 0 detected stores in Shoplist. This Markdown profile displays 0 public brand examples; it is not a complete customer list.

## Key facts
- Name: PopUp ‑ Sell by Weight
- Monitoring status: First-adopter watch
- Developer: Mad Valley Productions
- Developer profile: https://shoplist.co/app-developers/mad-valley-productions
- Shopify App Store URL: https://apps.shopify.com/popup-sell-by-weight
- Website: https://apps.madvalley.com
- Launch date: May 27, 2026
- Shoplist category: Selling in person - Other
- Free plan signal: Yes

## Pricing summary
Free: Free; Season-Pass: $4.99/month; Annual: $30/year

Shoplist has not yet found reliable public storefront evidence connecting a Shopify store to this app. This does not mean the app has no users. Some apps are new, admin-only, server-side, theme-independent, or otherwise difficult to detect from public storefront signals.


## App Signals
As of November 9, 2026:

- Stores running it: 0, 0.0% of the stores Shoplist tracks
- Store movement, last 28 days: +0 new stores, +0 returning, −0 removed, net 0 (estimated; 2 days held out of movement)
- Primary App Store category: Selling in person - Other, #28 (14-day median position)
- Listing reviews: 0

## Public callouts
- Sell by weight or by item — price calculates instantly at the point of sale
- Catalog stored on the device — opens instantly, no fetching data delays
- Simple catalog with no inventory required, works alongside Shopify
- Mix market items and existing store products in the same transaction
- Pause between seasons — your catalog data is waiting when you return
## Shopify App Store categories
- Selling in person - Other

## Data note
Profile updated: October 13, 2026. This is the profile revision date, not a guarantee that every store was checked on that date.
Public snapshot built: 2026-11-09 12:53:09.041285\+00
Detection metrics refreshed: 2026-11-09 10:00:00.198215\+00
Public app evidence date: 2026-10-13 11:05:09.892788\+00
This generated Markdown profile intentionally exposes only public, stable app-profile fields and a small public app-stack sample from Shoplist. It excludes private contact data, people data, internal scores, crawl provenance, full datasets, and unstable operational fields.

## Related links
- [HTML app profile](https://shoplist.co/shopify-apps/popup-sell-by-weight)
- [Shopify apps directory](https://shoplist.co/shopify-apps)
- [Shoplist data methodology](https://shoplist.co/data-methodology.md)