Last updated: May 2026 · Pricing and ratings verified from live Shopify App Store listings on May 4, 2026. Reviewed by the Libautech team — builders of Built for Shopify apps used by 5,000+ merchants across 50+ countries.
| App | Job | Rating | Starting Price | Best For |
|---|---|---|---|---|
| Trunk | Multi-Channel Sync | 4.9/950+ | $35/mo | Shopify + Etsy/Amazon/eBay multi-channel |
| Stock Sync | Multi-Channel + Supplier | 4.7/1,500+ | Free / $5/mo | Affordable supplier feed sync |
| Syncio Multi-Store Sync | Multi-Store Sync | 4.9/200+ | $29/mo per store | Brands with multiple Shopify stores |
| Multi Store Sync Power | Multi-Store Sync | 4.9/130+ | $14.99/mo | 2-5 stores, flat-rate pricing |
| Realtime Stock Sync | Supplier Feed Sync | 4.8/100+ | $14.99/mo | Dropshipping with webhook performance |
| Stock Sync (supplier mode) | Supplier Feed Sync | 4.7/1,500+ | Free / $5/mo | High-volume dropshipping at scale |
| QuickSync (Square) | POS-to-Online | 5.0/5,200+ | $9.99/mo | Square POS retailers |
| Shopify Sync for Clover | POS-to-Online | 4.5/180+ | $19/mo | Clover POS retailers |
Most roundups of Shopify inventory sync apps treat marketplace sync, multi-store sync, supplier sync, and POS sync as one category. They are not. A multi-channel marketplace sync app keeps inventory aligned between Shopify and Etsy, Amazon, eBay, Walmart, or TikTok Shop. A multi-store Shopify sync app handles inventory between two or more Shopify stores (typically regional storefronts). A supplier feed sync pulls inventory from external supplier sources (FTP, CSV, XML, API) into Shopify. A POS-to-online sync handles physical retail to e-commerce inventory alignment between Square, Clover, or Lightspeed POS and Shopify. Different mechanics, different sync directions, different reliability requirements.
The honest framing: Shopify inventory sync apps break into four distinct layers based on what they manage. Most stores need at most one layer based on actual operational complexity — single-channel Shopify-only stores don't need any sync app, multi-channel sellers need marketplace sync, and dropshippers need supplier feed sync. Multi-store sync matters specifically for brands running regional storefronts.
The first job is multi-channel marketplace sync — keep inventory aligned across Shopify, Etsy, Amazon, eBay, and other marketplaces. The mechanics: app connects to multiple marketplace APIs, monitors inventory changes, pushes updates between channels via webhook or scheduled sync. Best fit for multi-channel sellers running Shopify alongside one or more major marketplaces.
The second job is multi-store Shopify sync — sync inventory between two or more Shopify stores. The mechanics: app installs on multiple Shopify stores, configures master-satellite or bidirectional sync, runs webhook-based updates when inventory changes on any store. Best fit for brands running regional storefronts (US, EU, UK on separate Shopify stores) or B2C-plus-B2B operations.
The third job is supplier feed sync — pull inventory from supplier feeds into Shopify. The mechanics: app connects to supplier FTP, CSV, XML, or API endpoints, parses inventory data, pushes updates to Shopify on configurable schedules. Best fit for dropshippers and brands carrying third-party SKUs from multiple suppliers.
The fourth job is POS-to-online sync — align physical retail and e-commerce inventory. The mechanics: integration app pulls POS inventory data (Square, Clover, Lightspeed) and syncs with Shopify, or vice versa, with configurable sync direction. Best fit for retailers with existing POS hardware investments where Shopify is the e-commerce arm.
Rating: 4.9/950+ reviews · Pricing: From $35/mo · Best for: Multi-channel sellers running Shopify plus Etsy, Amazon, eBay, Square, or TikTok Shop
Trunk is the highest-rated multi-channel inventory sync app, with 4.9/5 across 950+ reviews. The app handles real-time webhook sync across Shopify, Etsy, Amazon, eBay, Square, BigCommerce, WooCommerce, and TikTok Shop, with sub-30-second sync windows that prevent overselling under high-velocity conditions. Bundle and kit support handles complex SKU relationships where one Shopify product is multiple Etsy listings or vice versa. Pricing starts at $35/mo and scales by SKU and order volume.
Trunk's value compounds for stores selling 100+ SKUs across 3+ marketplaces where manual inventory updates would consume daily operational hours. The app's webhook architecture handles flash sales and viral product launches that scheduled-batch competitors cannot manage. For merchants whose primary inventory pain is overselling across channels, Trunk is the standard answer in 2026.
Rating: 4.7/1,500+ reviews · Pricing: Free plan available, paid from $5/mo · Best for: Stores needing affordable supplier feed sync plus marketplace sync
Stock Sync is the most established inventory sync platform on Shopify, with 1,500+ reviews and 4.7/5 rating. The app handles supplier feed sync (FTP, CSV, XML, Google Sheets, API), marketplace sync, and basic multi-store sync. The free plan covers up to 1,000 products with one supplier feed; paid plans from $5/mo unlock more feeds, faster sync intervals, and additional channels. For dropshippers and brands managing supplier feeds, Stock Sync's affordability and broad feature set make it the practical default.
Trade-offs: Stock Sync's webhook reliability and real-time sync performance lag behind dedicated multi-channel apps like Trunk for the highest-velocity stores. Merchants doing $50K+/mo with active marketplace sales should validate sync performance under their specific load conditions before committing.
Rating: 4.9/200+ reviews · Pricing: From $29/mo per store · Best for: Brands running multiple Shopify stores with shared inventory
Syncio specializes in Shopify-to-Shopify inventory sync between multiple stores. The app handles master-satellite configurations (one source store pushes to multiple satellites) or bidirectional sync, with webhook-based real-time updates and conflict resolution rules. For brands running US, EU, UK regional Shopify stores, B2C-plus-B2B store pairs, or wholesale-plus-retail Shopify operations, Syncio handles the sync direction control that generic sync apps cannot. Pricing starts at $29/mo per store and scales by SKU and sync complexity.
Rating: 4.9/130+ reviews · Pricing: From $14.99/mo · Best for: Mid-market brands with 2-5 Shopify stores needing sync without per-store fees
Multi Store Sync Power competes with Syncio on multi-store Shopify sync but with flat-rate pricing rather than per-store fees. The app handles inventory, product data, and order sync between unlimited Shopify stores on higher tiers. For brands running 3-5+ regional storefronts where per-store pricing compounds, Multi Store Sync Power's flat pricing model becomes more cost-effective than Syncio's per-store model.
Rating: 4.8/100+ reviews · Pricing: From $14.99/mo · Best for: Dropshippers needing supplier feed sync with real-time webhook performance
Realtime Stock Sync handles supplier feed sync with webhook-based real-time architecture rather than scheduled batch sync. The app supports FTP, CSV, XML, JSON, and API supplier feeds, with sub-minute sync windows for stores doing high-velocity dropshipping. For dropshippers running supplier inventory through Shopify where overselling damages supplier relationships, Realtime Stock Sync's webhook architecture justifies the slight premium over scheduled-batch competitors.
Rating: 4.7/1,500+ reviews · Pricing: Free plan available, paid from $5/mo · Best for: Dropshippers needing affordable supplier feed sync at scale
Stock Sync's supplier feed features cover the primary use case for dropshippers — pull inventory from supplier sources (FTP, CSV, XML, API, Google Sheets) and push updates to Shopify on configurable schedules. The platform handles 100+ supplier integrations, custom field mapping, and price update sync alongside inventory. For dropshippers running 5,000+ SKUs across multiple supplier sources, Stock Sync's affordability and broad supplier compatibility make it the practical default at scale.
Rating: 5.0/5,200+ reviews · Pricing: Free plan available, paid from $9.99/mo · Best for: Retailers with Square POS hardware needing Shopify sync
QuickSync is the dominant Square-to-Shopify integration, with 5,200+ reviews and 5.0/5 rating. The app handles bidirectional sync of products, inventory, customers, and orders between Square POS and Shopify. Sync direction is configurable (Square-to-Shopify, Shopify-to-Square, or bidirectional), with field-level mapping for product attributes. For omnichannel retailers running Square POS plus Shopify e-commerce, QuickSync is the standard integration.
Rating: 4.5/180+ reviews · Pricing: From $19/mo · Best for: Retailers with Clover POS hardware needing Shopify sync
Shopify Sync for Clover handles product, inventory, and order synchronization between Clover POS systems and Shopify. Clover hardware is common in restaurants, salons, and small retailers. The integration covers product catalog sync, real-time inventory updates, and order export to Shopify for unified reporting. For merchants locked into Clover hardware contracts (typically 3-year terms with banks), this integration extends the hardware investment by adding Shopify e-commerce on top.
The decision tree for most merchants: single-channel Shopify-only stores don't need any sync app. Multi-channel sellers running Shopify plus 1-2 marketplaces should start with Trunk ($35/mo) for webhook-based reliability. Dropshippers need Stock Sync (free/$5/mo) or Realtime Stock Sync ($14.99/mo) for supplier feed sync. Multi-store brands need Syncio ($29/mo per store) or Multi Store Sync Power ($14.99/mo flat) depending on store count. POS retailers running Square or Clover hardware need QuickSync ($9.99/mo) or Shopify Sync for Clover ($19/mo).
Combined with Libautech's Bundles & Upsell, Sticky Add to Cart, and Announcement Bar (all included on the $9.99/mo Package plan), the sync-plus-conversion stack covers inventory operations and online conversion mechanics from one combined toolset. The Announcement Bar handles 'Selling fast' or 'Limited stock' urgency messaging that lifts conversion without interfering with sync operations.
The Libautech team builds Shopify apps used by 5,000+ merchants across 50+ countries, holding multiple Built for Shopify certifications. Inventory sync apps were evaluated using four criteria, weighted in order of merchant impact:
Sync architecture and latency. The single highest-impact factor is whether the app uses webhook-based real-time sync or scheduled-batch sync. Webhook architecture catches inventory changes in seconds; scheduled sync runs every 5-30 minutes. Apps were ranked higher when they support webhook sync at their entry-tier price point, not just on top tiers.
Channel and feed coverage. Multi-channel sync apps were evaluated by which marketplaces they support natively (Etsy, Amazon, eBay, Walmart, TikTok Shop, Square, BigCommerce). Supplier feed apps were evaluated by feed format support (FTP, CSV, XML, JSON, API, Google Sheets) and supplier API integrations.
Conflict resolution and direction control. Inventory sync apps fail when two channels both update the same SKU simultaneously. Apps were ranked higher when they offer configurable conflict resolution (last-write-wins, master-channel-wins, manual review) and clear sync direction control (one-way push, bidirectional, scheduled).
Review quality and recency. Apps with 4.5+ ratings across 100+ reviews scored highest, with bonus weight for reviews from the last 12 months. Documented sync failures or overselling incidents in recent reviews were penalized regardless of overall rating.
Webhook sync triggers an inventory update the moment a product is sold on any connected channel — sync windows are typically 1-30 seconds. Scheduled sync runs at fixed intervals (every 5, 15, or 30 minutes) regardless of activity. Webhook sync prevents overselling under flash sales and high-velocity conditions; scheduled sync is cheaper but introduces overselling risk during fast inventory changes.
No. Single-channel Shopify-only stores have no inventory to sync — Shopify's native inventory engine handles the single-channel case. Inventory sync apps become necessary the moment you add a second sales channel (Etsy, Amazon, eBay, marketplace, multiple Shopify stores, or POS hardware).
Trunk for higher-velocity stores or multi-channel sellers running Shopify plus Etsy plus Amazon — webhook sync prevents overselling. Stock Sync for cost-sensitive sellers or stores under $20K monthly revenue where the cheaper plan handles current load. The cost difference of $30/mo is meaningful at low revenue, irrelevant at high revenue.
Use Syncio ($29/mo per store) or Multi Store Sync Power ($14.99/mo flat for unlimited stores on higher tiers). Both handle webhook-based real-time sync between Shopify stores with configurable direction. The cost difference becomes meaningful at 3+ stores where Syncio per-store pricing compounds versus Multi Store Sync Power's flat rate.
For Amazon: aim for under 5-minute sync intervals to avoid suppressed-listing penalties. Amazon penalizes accounts with repeated overselling more aggressively than other marketplaces. For Etsy and eBay: 15-30 minute intervals work for most stores below $20K/mo. For all marketplaces during flash sales or viral product moments: webhook sync is the only reliable option.
Yes. Most sync apps support product data sync (titles, descriptions, images, pricing) alongside inventory sync, but this is optional. Many merchants run inventory-only sync to avoid product description conflicts between channels (where Etsy SEO is different from Amazon SEO is different from Shopify SEO).
Carefully. Bundle products are SKUs that combine multiple component SKUs — selling one bundle deducts inventory from each component. Apps like Trunk explicitly support bundle and kit relationships across channels. Generic sync apps often handle bundles incorrectly, leading to overselling of components when bundles sell. If your store uses bundles, validate bundle handling specifically before committing to a sync platform.
Yes, via API integrations. Stock Sync, Trunk, and Realtime Stock Sync all support custom API endpoints for ERP and warehouse system integration. For larger merchants running NetSuite, SAP, or custom warehouse management systems, dedicated middleware platforms (Celigo, Boomi, MuleSoft) handle complex sync requirements at higher cost and implementation complexity.
Libautech doesn't build inventory sync apps — the category requires deep integration with marketplace APIs and POS systems that fall outside the focus areas. The $9.99/mo Package plan (Sticky Add to Cart, Bundles & Upsell, Announcement Bar) complements sync platforms by handling Shopify-side conversion, urgency messaging ('Selling fast', 'Limited stock'), and AOV mechanics without interfering with inventory operations. Stack Libautech's apps alongside Trunk or Stock Sync for the conversion-plus-sync combination.
Most Shopify inventory sync mistakes come from choosing the cheapest option rather than the right one for your sync direction and velocity. Trunk's $35/mo for webhook-based marketplace sync prevents thousands in oversold-inventory refunds for any store doing $20K+ monthly revenue across 2+ channels. Stock Sync's free plan is real but reliability matters more than cost above $50K/mo. Multi-store and POS sync needs are specific — don't buy general-purpose sync platforms when Syncio or QuickSync handle your exact use case better. Validate sync performance under your specific load conditions before committing budget.
If you have built a Shopify app in the inventory sync category and want it considered for this list, reach out at hello@libautech.com. We update this guide as new apps prove out merchant outcomes.
