
Last Updated: April 30, 2026 | Reviewed by Devon Cox, President, ConversionTeam
We implemented a persistent shopping cart banner across their mobile site, keeping selected items visible throughout the customer journey.
Persistent mobile UI elements work because they keep purchase intent visible across every page transition - exactly what mobile sessions need. The kind of mobile-aware test design to look for when evaluating leading ecommerce CRO agencies on traffic-mix specialization.
Key Achievements:
Mobile traffic was increasing rapidly, but the conversion wasn't keeping up. Users were adding products to cart but failing to complete purchases.
We proposed adding a persistent shopping cart banner that would remain visible throughout the customer journey.
Cart Banner Features:
Test Parameters:



| Metric | Control | Variation 1 | Variation 2 |
| Users | 865,508 | 868,293 | 865,522 |
| Transactions | 1,466 | 1,501 | 1,583 |
| Conversion Rate | 0.17% | 0.17% | 0.18% |
| Revenue Per User | $1.48 | $1.49 | $1.55 |
| Revenue Lift | — | 1% | 5% |
| Confidence | — | 71% | 98% |
The persistent cart banner solved a mobile shopping problem by bridging the gap between browsing and purchasing. There were two factors behind its success:
Want to learn more about how we can optimize your mobile shopping experience? Let's discuss how our data-driven approach can boost your e-commerce revenue.
Appendix: Detailed Test Parameters and Statistical Analysis
Statistical Analysis
| Metric | Value |
| Confidence level | 98% |
| Z-score | 2.12 |
| P-value | 0.0169 |
| Conservative lift estimate | 5% |
| Test lift | 8% |
| Sample size | Over 1.7 million users |
| Test duration | Multiple weeks |
| Participation rate | Even split between variations |
Test Parameters
| Parameter | Details |
| Device targeting | Mobile only |
| Browser targeting | All major mobile browsers |
| User segments | Adult customers only |
| Page scope | Homepage and category pages |
Field Notes