King Checkout Validation vs Lynk
Two Shopify apps, side by side: detected stores, momentum, reviews, plans, listed features and who runs each. Store counts as of Nov 9, 2026 for King Checkout Validation, Oct 14, 2026 for Lynk.
The short answer
- Only King Checkout Validation lists a free plan.
- King Checkout Validation lists 13 features Lynk’s listing doesn’t mention, including Cart-based, Checkout alerts, Collection-specific.
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
- · Create and test validation rules
- · Free for development stores
Basic
- · Block PO box addresses
- · Live chat and email support
- · Require VAT numbers
- · Require house, apartment or suite number
Premium
- · All Basic features
- · Build regular expression rules
- · Combine cart and customer conditions
- · Detect non-Latin characters
- · Match keywords in checkout fields
- · Set checkout field length limits
Annual
Coverage counts what each App Store listing names. Every feature, checked off app by app, is in Shoplist.
See every featureUse checkout validation to check shipping and billing address fields before orders are placed. Block PO boxes, require house or apartment numbers, and check postcode/ZIP, email and VAT/tax ID formats. Match phone country codes to address countries. Set order limits by cart amount, quantity or weight, with conditions for products, customer tags and countries. Use keyword, regex and field-length checks.
Greek stores often need a customer's VAT number and company name to issue an invoice. The standard checkout does not collect these details, and custom checkout fields are only available on the Plus tier. Lynk adds an optional VAT section to your cart, available to every store. Customers who need an invoice enter their Greek or EU VAT number and company name.
- Verifies presence of house/apartment number in addresses
- Validates completion of customer's VAT number (Tax exemption)
- Filters out Post Office (PO) Box addresses
- Field Length Validation, Custom Keyword and Regular Expression Validation
- Add optional VAT and company-name fields to the cart
- Validate Greek VAT numbers with the AADE tax authority
- Validate EU VAT numbers with the VIES verification service
- Save the official company name and details on each order








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 | King Checkout Validation | Lynk |
|---|---|---|
| Detected stores | 1 | 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 | Home & Garden | Not published |
| Top store countries | Australia | Not published |
Reviews
| Measure | King Checkout Validation | Lynk |
|---|---|---|
| App Store rating | 5.0 ★ | Not published |
| App Store reviews | 20 | Not published |
| New reviews, 28 days | 0 | Not enough data |
| Reviewers a year or more in | Not enough data | Not enough data |
Pricing
| Measure | King Checkout Validation | Lynk |
|---|---|---|
| Free plan | Yes | Not listed |
| Lowest paid monthly plan | $4.99/month | No monthly plan listed |
| Longest free trial | 7 days | 7 days |
| Plans listed | 3 | 1 |
Listing
| Measure | King Checkout Validation | Lynk |
|---|---|---|
| Shopify category rank | #24 | #334 |
| Shopify App Charts | Not on this week’s charts | Not on this week’s charts |
| Built for Shopify | Yes | No |
| Launched | Mar 15, 2024 | May 28, 2026 |
| Languages | 1 | 2 |
| Developer | Lightcone | Lynk.gr |
FAQ
King Checkout Validation and Lynk: common questions
- Is King Checkout Validation or Lynk cheaper?
- Only King Checkout Validation lists a free plan. Shoplist compares base prices only between monthly plans in the same currency; usage charges and annual plans vary, so check each plan’s limits.
- What features does each app list that the other doesn’t?
- King Checkout Validation lists 13 the others don’t mention, such as Cart-based, Checkout alerts, Collection-specific, Custom messages. A feature missing from a listing may still be supported; this compares what each App Store listing says.
- 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 Nov 9, 2026 for King Checkout Validation, Oct 14, 2026 for Lynk; 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 Nov 9, 2026 for King Checkout Validation, Oct 14, 2026 for Lynk. 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.






