Login friction is silent churn. OTP made the front door invisible.
Comet is a digitally native Indian sneaker brand focused on delivering modern retail experiences through its e-commerce storefront. To align with mobile-first customer expectations and reduce login friction, we engineered a custom mobile number OTP authentication system that works natively within Shopify's customer validation framework.
The implementation required custom backend logic to map mobile numbers to Shopify customer accounts, structured handling of duplicate records, and authentication workflows consistent across both storefront and checkout — delivering a seamless, passwordless login experience without disrupting any existing order or account workflows.
Three people were experiencing the friction of authentication that didn't match how people actually want to access their accounts — a customer who couldn't remember an email, a support agent handling duplicate account confusion, and a brand manager whose mobile-first brand had an email-first login.
Frequent sneaker buyers attempting to log in before a drop were blocked by email-based authentication — unable to recall which address was used to register, they got locked out and missed time-sensitive launches entirely.
🔑 Email-based login causing access failures — customers missing drops and promotionsSupport agents handled multiple tickets each week from customers whose order history was fragmented across two accounts — the same phone number linked to different emails, requiring time-consuming manual resolution that still left customers with a poor experience.
📋 Duplicate account records from multiple email sign-ups with same phone numberDigital product managers at mobile-first brands found that email-based login was fundamentally mismatched to a Gen Z and young millennial audience — one that identified primarily by phone number and found password recall on mobile a genuine barrier to purchase.
📱 Email-first authentication mismatched to mobile-first Gen Z audience expectationsShopify's native authentication relies on email-based customer login workflows — a model that creates friction for Comet's mobile-first Gen Z audience. Dev's experience wasn't unusual: customers who shop across devices, register with multiple emails, and simply can't remember which credential they used for a specific store face a login wall at the worst possible moment — the start of a limited drop or a time-sensitive promotion.
The identity resolution complexity compounded the problem. Multiple customer records associated with the same phone number created support burden for Ishaan and data fragmentation for the brand. And the authentication inconsistency between storefront and checkout created a disjointed experience that Sanjana's product team needed to unify. The solution had to work within Shopify's validation framework without compromising account security or disrupting existing order workflows.
“A mobile-first brand with a login experience designed for email-first customers — creating friction at exactly the moment that should be frictionless.”
OTP authentication was engineered to remove the login friction that was silently costing Comet customers at their most important moments.
Designed and built a custom mobile OTP authentication flow integrated natively with Shopify customer accounts — Dev enters his phone number, receives an OTP, and is authenticated without remembering an email or password.
Human-CentricityBuilt a custom UI aligned with Comet's brand aesthetics delivering a seamless login experience across all storefront touchpoints — authentication feels native to the brand, not like a third-party overlay.
Human-CentricityImplemented backend logic managing email mapping while enabling customers to authenticate using mobile numbers — Shopify's customer records remain email-keyed while the authentication abstraction handles the mobile identity layer.
SustainabilityEngineered structured handling for multiple email records associated with the same phone number — identifying and surfacing the correct account for Ishaan's support cases and preventing future duplicate creation.
ResilienceExtended the OTP authentication workflow across checkout entry points — Sanjana's end-to-end consistency is achieved with the same mobile-first login experience from homepage to order confirmation.
SustainabilityLeveraged Shopify's secure validation mechanisms to maintain account integrity while abstracting the complexity from customers — security maintained, UX complexity eliminated.
ResilienceDev taps 'Login with mobile', enters his number, receives an OTP, and is in — before the drop timer reaches zero. The authentication experience matches the speed and urgency of sneaker culture. Login is no longer the barrier it was.
Ishaan handles fewer duplicate account tickets because phone-number-based identity prevents the multiple-email-per-customer fragmentation that caused them. When tickets do arrive, the identity resolution logic surfaces the correct account immediately.
Sanjana's product has a consistent authentication experience from storefront to checkout — the same mobile OTP flow, the same UI, the same seamless behavior. No jarring transitions or different login mechanisms at different points.
Comet's authentication now matches its identity — a Gen Z brand selling on mobile deserves mobile-native login. The OTP system reduces friction at the most critical access points in the customer journey.
Custom mobile OTP authentication for Shopify — passwordless login, identity resolution, and checkout consistency built for mobile-first D2C brands.