Merchant AI: Chatbots & Agents vs Sigma ‑ AI Shopping Assistant
Two Shopify apps, side by side: detected stores, momentum, reviews, plans, listed features and who runs each. Store counts as of Oct 13, 2026 for Merchant AI, Sep 3, 2026 for Sigma.
The short answer
- Only Merchant AI lists a free plan.
- Merchant AI lists 8 features Sigma’s listing doesn’t mention, including Behavior tracking, Cart recovery, Chat buttons.
Head to head
Free Plan
- · 1 AI agent
- · 1 MB knowledge base
- · 1 team seat
- · 20 messages / month
- · Website & file sources
Starter Plan
- · 1 AI agent
- · 15 MB knowledge base
- · 2 team seats
- · 400 messages / month
- · Advanced analytics
- · All source types
Pro Plan
- · 2,500 messages / month
- · 3 AI agents
- · 30 MB knowledge base
- · 5 team seats
- · Advanced analytics
- · All source types
Business Plan
- · 10 team seats
- · 5 AI agents
- · 60 MB knowledge base
- · 9,000 messages / month
- · Advanced analytics
- · All source types
Coverage counts what each App Store listing names. Every feature, checked off app by app, is in Shoplist.
See every featureMerchant AI installs on your Shopify store and indexes your products, collections, policies, and content, refreshing whenever your catalog changes. Shoppers ask questions and get answers grounded in your store data. They can see product recommendations, add to cart, look up an order, or start a return inside the chat. You set the agent's tone, refund posture, and escalation rules in plain English.
Sigma AI is your always-on AI shopping assistant that helps customers find products, track orders, and checkout faster. Unlike basic chatbots, it understands your entire product catalog and delivers personalized recommendations through natural conversation. Customers ask questions like "show me gifts under $50" and get instant product cards with images, prices, and one-click add-to-cart.
- Auto-syncs your products, collections, policies, and blog posts on install
- Recommends products and adds to cart inside the conversation
- Looks up orders, tracking, and starts returns without leaving chat
- Set your tone, refund posture, and escalation rules in plain English
- Smart product discovery - customers find products using natural language
- 24/7 automated support - answers questions about products and policies
- Conversation analytics and revenue attribution dashboard
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 |  Merchant AI |  Sigma |
|---|---|---|
| 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 | Merchant AI | Sigma |
|---|---|---|
| App Store rating | 5.0 ★ | Not published |
| App Store reviews | 1 | Not published |
| New reviews, 28 days | Not enough data | Not enough data |
| Reviewers a year or more in | Not enough data | Not enough data |
Pricing
| Measure | Merchant AI | Sigma |
|---|---|---|
| Free plan | Yes | Not listed |
| Lowest paid monthly plan | $25/month | No monthly plan listed |
| Longest free trial | 14 days | Not listed |
| Plans listed | 4 | Not published |
Listing
| Measure | Merchant AI | Sigma |
|---|---|---|
| Shopify category rank | #675 | Not enough data |
| Shopify App Charts | Not on this week’s charts | Not on this week’s charts |
| Built for Shopify | No | No |
| Launched | May 21, 2026 | Jan 13, 2026 |
| Languages | 1 | 1 |
| Developer | Cross Digital Ltd | MerchantAI |
FAQ
Merchant AI and Sigma: common questions
- Is Merchant AI or Sigma cheaper?
- Only Merchant AI 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?
- Merchant AI lists 8 the others don’t mention, such as Behavior tracking, Cart recovery, Chat buttons, Chat window. Sigma lists 2 the others don’t mention, such as Color and font, Live chat. 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 Oct 13, 2026 for Merchant AI, Sep 3, 2026 for Sigma; 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 13, 2026 for Merchant AI, Sep 3, 2026 for Sigma. 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.