Verified Expert in Product Management
Kosta has built, validated, and scaled compelling mobile/web products in SaaS, marketplace, and membership eCommerce startups. He’s overseen an exit and rapid scaling by leading two business pivots, while also serving clients with comprehensive private banking solutions. Skilled in strategy (vision, levers), planning (roadmaps, GTM, MVP), and execution (prioritization, A/B tests), Kosta blends empathy with a data-driven mindset to inspire teams, solve users’ problems and add business value.
Senior Product Manager
- Drove core customer outcomes, such as finding relevant products faster (0.5 fewer clicks/add) and covering a wider variety of the household shop (1.5x more diverse SKUs/order, +8% avg. order value) through various initiatives.
- Defined and built a membership MVP in eight weeks, resulting in hundreds of members, an exponential growth trajectory, and a shift of the company-wide focus to Bother Club.
- Improved transparency, decision speed and quality, collaboration, and ROI through implementing processes (e.g., continuous discovery and stakeholder checkpoints) and templates (e.g., specs and workshop frameworks) for ways of working.
- Drove conversion and retention to all-time highs (+10% retention, 2x conversion) through initiatives such as lower minimum order, box savings, product landing pages, and more.
- Increased ARR by more than 7x and members by more than 10x through the build and development of high-achieving teams that shipped impactful features for our membership platform (such as free trials and member tiers on iOS, Android, web, and back end).
- Spearheaded the go-to-market strategy for the pivot into membership by managing priorities across multiple stakeholders, aligning strategy with KPIs and execution, making data-driven decisions, and conducting user research.
- Built and led a team of two product managers and two UI/UX designers by sharing best practices for specs, UX, tickets, stakeholder management, and personal growth.
- Improved member retention by 10% through features such as cancellation flow and dynamic win-back offers.
- Increased the conversion (60%) from download to sign-up through the implementation of social sign-ups and new flows.
- Improved transparency, accountability, and team alignment by unifying the tools our teams use and implementing new production processes with rigorous documentation.
- Achieved a growing 6-figure revenue through building new product lines from the ground up (such as Gallery Frames, Photobooks, and Photo Prints).
Senior Manager, Product Strategy
- Led the successful rebranding and pivot into gaming-as-a-service by developing the go-to-market strategy and prioritizing the product roadmap, aligning inputs from management, engineering, marketing, and sales.
- Scaled the platform from 300,000 DAU to over 2 million DAU by building product specs, executing the strategy, and delivering the roadmap, leading to the first paying clients and $400,000 in revenue.
- Increased player LTV and retention for mobile game developers (such as +5% in revenue in Rail Rush and +130% in 7-day retention in Triple Town) by scoping and shipping the web portal and three products built as part of the SaaS platform.
- Improved operational efficiency by managing and modeling the company's strategic financial forecasting.
Analyst, Private Banking
JP Morgan Chase
- Advised a broad range of high-net-worth families in the areas of banking, borrowing, investing, and estate planning by supporting three financial advisors with $600 million in assets under management.
- Contributed to the acquisition of $200 million in new client assets by deploying highly specialized Monte Carlo simulations for wealth projections and building portfolios tailored to clients' objectives and needs.
- Identified and qualified more than 2,000 individual and institutional high-net-worth prospects through extensive research and cross-referencing of local mortgages and other data.
Conversion Optimization at Bother
Doubled conversion and thus reduced CAC and accelerated growth.
• Dove deep into Tableau and our data and sliced data anew.
• Watched video recordings on Hotjar with 'abandoned basket' sessions.
• Conducted targeted user research and interviews on the matter.
• Synthesized insights from all the above actions and then ran brainstorming sessions with my team on the core sub-problems that were popping up.
• Prioritized solutions in all areas, from UI/UX (e.g., show savings in the basket, rescue discount codes) to system performance, removing and simplifying components, core behavior (e.g., lowering minimum order value), and much more.
TouchNote | Pivot to Membership: Strategy Definition, Product-market Fit, and Platform Scaling
Successfully pivoted the business into a membership/subscription model, scaling ARR to 7x and membership to 10x.
• Managed a team of seven developers, one designer, one marketer, and one QA engineer through design, development, testing, growth, and support.
• Utilised an Agile methodology, leading sprint planning, project kick-offs, backlog grooming, sprint retros, priority planning, daily standups, and post-mortems, delivering to tight deadlines through effective prioritization based on data-driven decisions and internal strategic goals.
• Developed a theme-based roadmap with end-to-end solutions by conducting initial deep-dive market and competitor research, user research and testing, functional product specs, wireframes and UX, pricing, suppliers and integrations, A/B tests, analytics, and growth, overseeing all development stages, and leading functional testing, QA testing, training, and all post-go-live support for more than 15 major features over a 3-year timespan.
Examples of the features we shipped: free trials, monthly payments, cancellation flow, member tiers, upgrades/downgrades, pricing tests, stickers, and filters.
TouchNote | New Process Implementation and Change Management
Spearheaded a vast increase in transparency, accountability, fluidity, performance, and stakeholder satisfaction.
I was fully responsible for taking an as-is process for getting initiatives into development and redesigning it into a clearer, more concise, and more fluid process, unifying our tools.
Going fully remote hindered visibility and accountability and exposed gaps in the process.
Our "product machine" takes a series of inputs, applies certain actions to them, moves them across people and departments, and produces outcomes. Digging deeper, it's about illuminating every step, milestone, and machine owner.
After observing the as-is, I got to the root cause: our inadequate documentation and the variety of tools used. Then we implemented Monday.com and a clear-and-concise product process starting with a one-pager, then Discovery, ICE prioritization, tech discussion, a full spec, allocation of resources based on priority/capacity, and post-release analysis to compare observed KPIs with the plan.
We produced a standardized framework for feeding requirements into the backlog, a shared understanding of effort and value, and a clear idea of an initiative's status and delivery date. We ended up with a happy team, satisfied stakeholders, and rapid execution.
Fuel Powered | Launch of a Developer Web Portal
Increased the percentage of mobile game players' retention and LTV through designing, creating, and successfully launching Fuel Powered's developer web portal.
• Served as a key member in the design, creation, and successful launch of Fuel Powered's developer web portal, built to allow developers to undertake actions for their games, configure game variables, enable tournaments, and access all necessary game data and information, removing these responsibilities from internal resources.
• Co-led, with a fellow product manager, a team of two developers through the design, architecture, and implementation, and completely designed it (UI/UX, DB architecture, API architecture, security) from the ground up.
This product resulted in quicker turnaround times from game strategy conception to implementation, a broader and faster ability to conduct tests and intuitively view results, a 1-stop shop for developers to see and digest all relevant documentation, and finally, a method for constant and consistent feedback to facilitate continuous improvement.
TouchNote | Product Management for the Launch of All Physical Products
Achieved a growing 6-figure revenue, improved member retention, and product differentiation through launching three new products from the ground up (Gallery Frames, Photobooks, and Photo Prints).
• Managed a team of four developers, one designer, one marketer, and one QA engineer through design, development, supplier integrations, testing, growth, and support.
• Utilized the Agile methodology, leading sprint planning, project kick-offs, backlog grooming, sprint retros, priority planning, daily stand-ups, and post-mortems, delivering to tight deadlines through effective prioritization based on data-driven decisions and internal strategic goals.
• Developed end-to-end solutions by conducting initial deep-dive market and competitor research, user research and testing, functional product specs, wireframes and UX, pricing, suppliers and integrations, A/B tests, analytics, and growth, overseeing all development stages, and leading functional testing, QA testing, training, and all post-go-live support.
Master of Science Degree in Operations Research
Columbia University -— School of Engineering and Applied Science - New York, NY, United States
Bachelor's Degree in Finance and Accounting
Athens University of Economics and Business - Athens, Greece
Chartered Financial Analyst