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Streamlining authentication to reduce fraud and improve experience
Role
Lead Designer
Timeline
6 Months, Q4 2024 + Q1 2025
Project type
Account Integrity, Identity
Contribution
Product Strategy, UX/UI Design, User Workflows, UX Research
OVERVIEW
Path Forward was the Identity team’s first product in collaboration with design and product, aimed at reducing SMS fraud and verification costs while improving authentication. We tested two variants of the sign-up and login flows, prioritizing email login and delaying SMS OTPs to curb fraud and unnecessary spending, while maintaining conversion and creating a smoother, more reliable experience for new and existing users.
RESPONSIBILITIES
I led end-to-end design for Tinder’s authentication, partnering closely with Product and Eng to balance the user experience with backend and cost constraints. My work focused on mapping complex system flows, simplifying identity verification, and aligning cross-functional teams on a scalable, trust-driven experience.
CHALLENGE
Identifying weak points in login and sign up flows
PROBLEM
Tinder faced $28M in SMS fraud in 2024, with bad actors quickly bypassing existing defenses. The authentication process needed an update, prompting a discovery phase that revealed three key areas driving the issues.
01
Flow Vulnerability
The flow to get to the OTP screen required fewer than three taps, which made it susceptible for abuse. Simple for users but easily exploited by bad actors, driving up SMS costs.
02
Single API Limitation
Since phone numbers were the only identifier, OTPs were sent to all entries-even fake ones. This let bad actors exploit the flow, with high drop-offs and invalid numbers confirming SMS pumping.
03
Gap in User Guidance
Messaging and copy were inconsistent with Tinder’s brand voice, lacked clarity on feedback, and didn’t cover edge or niche use-cases.
HMW reduce SMS fraud and costs while keeping authentication secure, minimizing friction, and maintaining strong registration and login conversion for legitimate users?
STRATEGY
Outlining the ideal experience
DEFINE SUCCESS
Before diving into designs, my product manager and I collaborated with analytics and key stakeholders to define clear success metrics. This ensured we could measure the impact of the changes and align on what “success” would look like for both the business and our users.
REDUCE
SMS Cost & Fraud
MAINTAIN
Conversion & Retention
IMPROVE
User Experience & Clarity
EXPECT
Fraud Mitigation
*Exact success metrics are under NDA
A/B IDEATION & CHALLENGES
I was the sole designer working across two separate projects addressing the same authentication problem, each led by a different PM and engineering lead.
With conflicting ideas between the two teams, I mapped user workflows paired with the multi-facotr authentication logic, constraints, and developed <5 use-cases to align both teams. This enabled a data-driven A/B test of the two variants against the current experience.
VARIANT 1
Dynamic email first experience
Prioritizes email for both sign-up and login, delaying SMS OTP until after email verification. Uses a single API and covers 5–6 authentication use cases, providing a consistent, user-centered experience while reducing SMS costs.
VARIANT 2
Reduce SMS sends for login
Splits the API for better backend control and user detection. Most users follow Variant 1’s email-first strategy for account creation, while login for existing users begins with phone number; only numbers linked to existing accounts receive SMS OTP.
DESIGN APPROACH
Designing for clarity and control
CROSS FUNCTIONAL ALIGNMENT & BUSINESS IMPACT
Collaborated with the Identity teams to translate API and routing constraints into user-centered solutions. Evaluated proposals for risk and friction through competitor analysis and mock flows, ensuring decisions balanced reducing SMS fraud and costs with maintaining a clear, seamless user experience.
HOLISTIC FLOW AND USE-CASE MAPPING
Close collaboration allowed me to map out the current and proposed authentication flows to identify dead ends, edge cases, and high-friction points. Paired API logic with user behavior to create 5–6 unique use-case scenarios, ensuring both new and existing users had seamless, technically feasible journeys.
*Blurred the images for confidentiality purposes.
CONTENT AND COMMUNICATION STRATEGY
Partnered with a Sr. Content Designer, we revised and developed content across new and existing screens to improve clarity, transparency, and guidance. Focused on reducing confusion, unblocking deadends, and improving comprehension in high-risk flows.
AS OF 09/2025
Ongoing A/B test shows early SMS cost reduction with stable user conversion
RESULTS AND IMPACT
The Path Forward A/B test has launched in August 2025, targeting high-cost and high-fraud regions, including Indonesia, Philippines, Peru, and Mexico. Early data shows promising trends:
SMS Costs: Initial results suggest a ~10% decline in SMS sends in some regions, with projected savings of $1.17M per quarter across targeted geos.
User Experience & Conversion: Registration and reactivation rates remain stable, indicating no negative impact on legitimate users.
Next Steps: The experiment is being extended to gather conclusive data, ensuring long-term impact and insights before full rollout.
CONCLUSION
What I learned leading identity and authentication designs
This project gave me the opportunity to deeply collaborate with Tinder’s Identity team, navigating the ambiguity of timelines, expectations, and experiment rollouts. As their first product, it required patience, education, and constant alignment across multiple teams. I was committed to understanding backend logic and the team’s workflows to communicate effectively and identify areas for improvement.
Balancing technical constraints, content, and policy considerations while advocating for clear, user-centered experiences reinforced my approach to solving complex systems problems that serve both users and business needs. In hindsight, earlier engineering involvement and collaborative workshops could have streamlined alignment and clarified logic flows sooner.
The team recognized my initiative, highlighting my ability to “Own It” and shape product decisions from both technical and user-focused perspectives. This project was challenging, but ultimately one of the most rewarding experiences in my career.
A highlight from a Tinder Huddle recognizing my embodiment of the company value “Own It" from this project ❤️🔥
