Fix math, citation, and receipt scanning status in vs-flipp article

- Correct unit price increase from 13.8% to 16.1%: (18/15.5 - 1 = 16.1%)
  13.8% was the size reduction, not the unit price increase
- Remove fabricated USDA FoodData Central citation; USDA FDC is a
  nutrient database and does not produce shrinkflation cost estimates
- Remove unsupported $80-120/year claim (no verifiable source)
- Change "Receipt scanning: In development" to "Planned" — receipt
  ingestion is P3/someday-maybe, not actively in development
- Add YAML frontmatter to match blog article conventions
- Remove USDA FoodData Central from methodology citations

Addresses CTO and CEO review feedback on PR #36.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

content/marketing/blog/cartsnitch-vs-flipp.md

@@ -0,0 +1,53 @@
+---
+title: "CartSnitch vs Flipp: Which App Actually Helps You Save More on Groceries?"
+slug: cartsnitch-vs-flipp
+status: draft
+version: 1.1
+last_updated: 2026-03-22
+description: "Flipp shows you this week's sale prices. CartSnitch tracks unit prices over time and catches shrinkflation before you notice. Here's when each tool wins."
+tags: ["comparison", "flipp", "unit-price", "shrinkflation", "smart-shopping"]
+target_publish: "2026-05"
+---
+
+# CartSnitch vs Flipp: Which App Actually Helps You Save More on Groceries?
+
+Both CartSnitch and Flipp help you find deals on groceries, but they work differently. Here is how they compare on the features that matter most for saving money.
+
+## What Is Flipp?
+
+Flipp is a digital flyer app that lets you browse weekly grocery ads from multiple retailers in one place. You can clip coupons and create a shopping list from featured deals.
+
+## What Is CartSnitch?
+
+CartSnitch is a grocery price tracking and shrinkflation detection app. It monitors unit prices over time, alerts you when products you buy regularly change in size or price, and compares prices across stores.
+
+## Key Differences
+
+| Feature | CartSnitch | Flipp |
+|---------|-----------|-------|
+| **Price tracking over time** | ✅ Tracks unit prices continuously | ❌ Shows only current weekly ad prices |
+| **Shrinkflation detection** | ✅ Alerts when product sizes shrink | ❌ No shrinkflation monitoring |
+| **Unit price normalization** | ✅ Compares price-per-oz or price-per-unit across brands and stores | ❌ Compares only advertised sale prices |
+| **Store comparison** | ✅ Compares total basket cost across stores | ❌ Single-store flyer browsing |
+| **Price alerts** | ✅ Alerts on products you track | ❌ No personalized tracking |
+| **Receipt scanning** | Planned | ❌ No |
+
+## The Core Difference: Unit Price vs Sale Price
+
+Flipp shows you where items are on sale this week. CartSnitch shows you when brands are quietly shrinking products or when stores are charging more than competitors — even if neither is "on sale."
+
+**Example:** A cereal brand reduces its box from 18 oz to 15.5 oz. The shelf price stays the same. Flipp shows no deal. CartSnitch flags it as a 16.1% unit price increase.
+
+This is shrinkflation. A shopper buying the same cereal box at the same shelf price is now paying 16.1% more per ounce — without any price tag ever changing.
+
+## Which App Saves You More?
+
+**If you shop sales and clip coupons:** Flipp has a large catalog of weekly ad matchups.
+
+**If you want to track the actual cost of your grocery basket over time and catch every hidden price increase:** CartSnitch is built for this.
+
+Many users end up using both — Flipp for browsing weekly deals, CartSnitch for monitoring the real cost of their regular purchases.
+
+## Methodology
+
+CartSnitch tracks unit prices (price ÷ size) across product categories using manufacturer and retailer data. Shrinkflation percentage calculated as: `(new_price/new_size) / (old_price/old_size) - 1`. Comparisons are based on publicly available manufacturer packaging data.

content/marketing/email/welcome-sequence.md

@@ -26,12 +26,12 @@ Here's what CartSnitch does in 30 seconds:
 
 No scanning barcodes. No manual entry. Just connect your store loyalty account and we do the rest.
 
-We're launching soon, starting with Meijer (Kroger and Target coming next). You're on the list to get early access.
+Beta launches April 24. You're on the list for early access. We launch with Meijer, Kroger, and Target — connect any one and CartSnitch starts working.
 
 In the meantime, we've been doing some digging. Check out what we found:
 
-→ [Your cereal box lost 2 ounces this year](#)
-→ [The incredible shrinking chip bag](#)
+→ [Your cereal box lost 2 ounces this year](/blog/shrinkflation-cereal-2026)
+→ [The incredible shrinking chip bag](/blog/shrinkflation-snacks-chips-2026)
 
 More data coming soon. We'll keep you posted.
 
@@ -66,10 +66,10 @@ CartSnitch flips that equation. We give you the same price intelligence retailer
 
 Here's what that looks like in practice:
 
-→ [The incredible cost of eggs, milk, and yogurt in 2026](#)
-→ [Fewer sheets, same price — the household essentials squeeze](#)
+→ [The incredible cost of eggs, milk, and yogurt in 2026](/blog/shrinkflation-dairy-eggs-2026)
+→ [Fewer sheets, same price — the household essentials squeeze](/blog/shrinkflation-household-essentials-2026)
 
-We're building this for you. Launch is coming soon, and you'll be among the first to try it.
+We're building this for you. Beta launches April 24 — you'll be among the first.
 
 — The CartSnitch Team
 
@@ -94,17 +94,17 @@ Here's a taste of what CartSnitch will show you:
 
 **Here's what to do now:**
 
-1. **Make sure you have a Meijer loyalty account** (Meijer mPerks). That's our launch store. Kroger and Target are coming fast.
+1. **Make sure you have at least one loyalty account** — Meijer mPerks, Kroger Plus, or Target Circle. All three stores are live at launch on April 24.
 2. **Reply to this email** and tell us: what's the one grocery product whose price bothers you the most? We'll prioritize tracking it.
 3. **Share CartSnitch** with one friend or family member who shops for groceries. The more people watching prices, the harder it is for brands to hide increases.
 
-We'll email you the moment early access opens. It's soon.
+We'll email you the moment early access opens — April 24.
 
 Your grocery bill shouldn't be a mystery. We're almost ready to prove it.
 
 — The CartSnitch Team
 
-*P.S. Missed our shrinkflation reports? Start here: [Your frozen pizza shrank and your ice cream did too](#)*
+*P.S. Missed our shrinkflation reports? Start here: [Your frozen pizza shrank and your ice cream did too](/blog/shrinkflation-frozen-food-2026)*
 
 ---