ES Back in Stock Notify Me! vs Smile: Loyalty Rewards Programfor Shopify (2026)
ES Back in Stock Notify Me! and Smile: Loyalty Rewards Program, while both operating within the Shopify ecosystem and sharing the 'Notifications' category, cater to vastly different merchant needs and objectives. ES Back in Stock focuses on recapturing lost sales due to out-of-stock inventory by leveraging AI-powered notifications and on-site elements. It helps merchants directly address immediate revenue losses caused by stockouts. Smile, conversely, is a broader loyalty and retention solution designed to cultivate long-term customer relationships through rewards, VIP tiers, and referral programs. Its core purpose is to increase customer lifetime value and brand loyalty.
At a Glance
ES Back in Stock Notify Me!
474 reviews
Smile: Loyalty Rewards Program
3,992 reviews
Detailed Overview
ES Back in Stock Notify Me!
Recover sales with AI inventory alerts(email & SMS), popups, forms, and product page sections.
Key Features
- AI-powered automatic email/SMS notifications reach customers at the right time
- Show button and popup on out-of-stock product & collection pages
- Edit email template freely in block section
- Multiple languages templates
- Inventory alert per warehouse / location
Smile: Loyalty Rewards Program
Launch a loyalty program in minutes — with points, rewards, VIP tiers, referrals and more.
Key Features
- Create a powerful loyalty program in minutes — points, VIP, referrals & more
- Customize every detail to match your brand's look and feel
- Embed loyalty on product pages, at checkout, with a modern loyalty page
- Loyalty Hub: Offer the ultimate home for rewards inside customer accounts
- Deeply integrated with Klaviyo, Judge.me, Gorgias and 30+ other tools you love
Feature Comparison
| Rating | 4.9/5 | 4.9/5 |
Rating ES Back in Stock Notify Me!4.9/5 Smile: Loyalty Rewards Program4.9/5 | ||
| Reviews | 474 | 3992 |
Reviews ES Back in Stock Notify Me!474 Smile: Loyalty Rewards Program3992 | ||
| Core Function | Out-of-Stock Notifications (AI-Powered) | Loyalty & Rewards Program |
Core Function ES Back in Stock Notify Me!Out-of-Stock Notifications (AI-Powered) Smile: Loyalty Rewards ProgramLoyalty & Rewards Program | ||
| Target Merchant | Merchants with frequent stockouts and lost sales | Merchants focused on customer retention and long-term value |
Target Merchant ES Back in Stock Notify Me!Merchants with frequent stockouts and lost sales Smile: Loyalty Rewards ProgramMerchants focused on customer retention and long-term value | ||
| Key Feature Focus | AI-driven email & SMS timing, on-site widgets | Points, VIP tiers, referrals, customization |
Key Feature Focus ES Back in Stock Notify Me!AI-driven email & SMS timing, on-site widgets Smile: Loyalty Rewards ProgramPoints, VIP tiers, referrals, customization | ||
| Integration Emphasis | Native product page sections | Klaviyo, Judge.me, Gorgias integration |
Integration Emphasis ES Back in Stock Notify Me!Native product page sections Smile: Loyalty Rewards ProgramKlaviyo, Judge.me, Gorgias integration | ||
| Value Proposition | Recapture immediate lost sales | Increase customer lifetime value |
Value Proposition ES Back in Stock Notify Me!Recapture immediate lost sales Smile: Loyalty Rewards ProgramIncrease customer lifetime value | ||
| Ease of Use | Quick setup, 24/7 live chat support | Launch a program in minutes |
Ease of Use ES Back in Stock Notify Me!Quick setup, 24/7 live chat support Smile: Loyalty Rewards ProgramLaunch a program in minutes | ||
Our Verdict
If a merchant's primary concern is recovering lost revenue due to products being out of stock, and they are looking for an AI-powered solution to intelligently notify customers, ES Back in Stock Notify Me! is the clear choice. Its strength lies in its focus on inventory management and timely communication to address immediate sales opportunities. On the other hand, if a merchant prioritizes building a long-term, engaged customer base through loyalty programs, rewards, and VIP tiers, Smile: Loyalty Rewards Program is the superior option. Its robust features and integrations offer a comprehensive approach to customer retention.
Common Questions
Which app is better for increasing immediate revenue?
ES Back in Stock Notify Me! is better for increasing immediate revenue by recovering lost sales from out-of-stock items through timely notifications.
Which app is better for building long-term customer loyalty?
Smile: Loyalty Rewards Program is better for building long-term customer loyalty through rewards programs, VIP tiers, and referral incentives.
Do both apps offer email marketing capabilities?
While both can trigger email notifications, Smile focuses more on email marketing integrated with Klaviyo, whereas ES Back in Stock primarily uses email for stock notifications.
Which app is easier to integrate into a theme?
ES Back in Stock Notify Me! offers native product page sections for Online Store 2.0, potentially making it easier to integrate directly into the theme.
Can both apps be used together?
Yes, they address different aspects of sales and customer relationships and can be used in tandem. ES Back in Stock handles short-term inventory issues, while Smile fosters long-term customer loyalty.
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