modlet: Block PO Box & Lockers vs PS: Checkout Rules
Two Shopify apps, side by side: detected stores, momentum, reviews, plans, listed features and who runs each. Store counts as of Oct 31, 2026 for modlet, Oct 14, 2026 for PS.
The short answer
- On the Shopify App Store: modlet 5.0 from 2 reviews and PS 5.0 from 1 reviews.
- Both list a free plan. Paid plans start at $7.99/month for modlet and $29.99/month for PS.
Head to head
Momentum
New reviews each month
Review pace is the clearest public read on how fast an app is winning new merchants.
Free
- · Address Simulator & Testing Tool
- · Block PO Boxes globally (Instant setup)
- · Native & Secure Checkout Validation
- · Up to 250 Store Orders per Month
Pro
- · Country & Region Whitelisting
- · Custom Error Messages & Translations
- · Granular Pattern Rules
- · Product Exemptions
- · Shipping Method Filtering
- · Unlimited Orders & Address Validations
Enterprise
- · 1-on-1 Workflow & Strategy Configuration
- · Dedicated Technical Account Manager
- · Guaranteed Custom SLA & Compliance Help
- · On-Demand Custom Data Exports & Reports
- · Priority Custom Feature Development
- · White-Glove Setup & Dedicated Onboarding
Free
- · PO Box blocking in 10+ languages
- · Social CTA: WhatsApp, IG, FB, X, TikTok
- · Thank-you verification banner
- · Unlimited orders, 1 active rule
- · Your own custom error message
Pro
- · Blocked-orders log with CSV export
- · Checkout banners with conditions
- · Everything in Free
- · One-click product upsell at checkout
- · Post-purchase survey saved to the order
- · Savings dashboard + analytics
Pro Annual
- · All 5 validation rules, not just PO Box
- · Everything in Pro, billed yearly
- · Lock in your price for 12 months
- · One-click product upsell at checkout
- · Post-purchase survey saved to the order
- · Save 33% vs paying monthly
Coverage counts what each App Store listing names. Every feature, checked off app by app, is in Shoplist.
See every featureProtect your shipping margins with reliable, global PO Box blocking. Built natively into Shopify Checkout, it physically blocks checkout completion for restricted addresses—ensuring 100% reliability. Why offer a generous free tier? Built by a veteran cloud architect, our highly efficient infrastructure keeps costs low, and we love helping new stores get off the ground.
Most stores pay one app to stop bad addresses, another to upsell at checkout, and a third to survey buyers. That is three bills and three scripts in one checkout. This app does all three. Block PO Box, Postfach and Packstation addresses in 10+ languages, require a house number, and restrict zip codes, countries, or order values. Add one-click upsell offers from a collection or your best sellers.
- Block PO Boxes, Lockers, and Military Addresses to prevent failed deliveries.
- Stop expensive UPS/FedEx carrier return fees instantly.
- Native Shopify Checkout integration—unhackable with zero theme code.
- Exempt specific countries or shipping methods from blocking rules.
- Block PO Box, zip code, country, and order value violations at checkout
- Hide, rename, and reorder shipping and payment methods
- Add checkout banners and Thank You page blocks with live preview
- Track blocked orders and checkout violations in real-time analytics
All the numbers
Every figure, side by side
A green dot marks the app ahead on a measured figure. Estimates, gaps and apps that leave no storefront trace never take the lead.
Adoption
| Measure |  modlet |  PS |
|---|---|---|
| Detected stores | Not published | Not published |
| Net store change, 28 days | 0 | 0 |
| Stores added, 28 days | Not enough data | Not enough data |
| Big-brand share | Not enough data | Not enough data |
| Top store categories | Not published | Not published |
| Top store countries | Not published | Not published |
Reviews
| Measure | modlet | PS |
|---|---|---|
| App Store rating | 5.0 ★ | 5.0 ★ |
| App Store reviews | 2(ahead) | 1 |
| New reviews, 28 days | Not enough data | Not enough data |
| Reviewers a year or more in | Not enough data | Not enough data |
FAQ
modlet and PS: common questions
- Is modlet or PS cheaper?
- Both list a free plan. Paid plans start at $7.99/month for modlet and $29.99/month for PS. Shoplist compares base prices only between monthly plans in the same currency; usage charges and annual plans vary, so check each plan’s limits.
- Which has better reviews, modlet or PS?
- On the Shopify App Store: modlet 5.0 from 2 reviews and PS 5.0 from 1 reviews.
- Where does this comparison’s data come from?
- Shoplist crawls Shopify storefronts to detect which apps each store runs, and reads each app’s Shopify App Store listing for reviews, pricing, features and integrations. Store counts are as of Oct 31, 2026 for modlet, Oct 14, 2026 for PS; estimated figures are labeled.
How Shoplist compares apps
Store counts come from Shoplist’s crawl of Shopify storefronts, which detects the apps each store runs; they are as of Oct 31, 2026 for modlet, Oct 14, 2026 for PS. Reviews, ratings, plans, features and integrations come from each app’s Shopify App Store listing. 28-day figures are labeled when estimated, and a figure that is missing or estimated never decides who leads. Read the methodology.