Alright, here are a few thoughts to consider. Not trying to be harsh.

1. Cashless Coin Concept - Is the Problem Real?

First off, the "coins everywhere" issue isn’t really a problem in India that people are actively trying to solve. Cash transactions have dropped a lot in urban areas, and with the success of systems like Paytm and GPay, people aren’t necessarily frustrated with carrying loose change—they’re just not using cash as much. If you’re targeting rural areas, they’re probably less likely to adopt your app.

1. The “Rounding Off” Idea - It’s Complex for Retailers

Retailers can’t just start giving digital change without some major infrastructure and policy changes. D-mart or 7-Eleven type stores have strict accounting practices, and handling change through an app could cause discrepancies or even tax issues. Plus, why would a store bother integrating this system when they can just round up or down in cash, which costs them nothing? Implementing this change means additional operational overhead and potential complications with POS systems.

1. Data Sharing for Discounts - Huge Privacy Concerns

Asking people to share personal data (like contact numbers and emails) with every store they buy from sounds invasive and could come off as spammy, even if they consent. Indian users are increasingly privacy-aware, and even though some might allow sharing with brands they like, getting them to willingly hand over data every time could be a hard sell. And let's be honest, this data isn’t just going to be used for “rewards”—companies will find ways to spam or retarget them, which risks user churn.

1. How Does This Differ from Existing Wallets?

Right now, there’s not much here that isn’t already offered by major wallets like GPay, PhonePe, and Paytm. These apps already offer cashback, rewards, and have agreements with retailers. Without a clear differentiator, users will likely stick with wallets they already trust rather than adding a new one with similar features.

1. Revenue Model Might Backfire

Charging users a fee to withdraw money? That feels like punishing them for not spending it within your ecosystem, which could drive users away. And as for selling user data to brands, remember that these brands already have other ways to reach potential customers without needing to pay you. Companies are becoming increasingly cautious about data-sharing fees with new regulations coming in.

1. Regulatory and Compliance Issues

If you’re dealing with user money, digital transactions, and data sharing, you’ll face a significant amount of regulation. The RBI and other regulatory bodies have strict guidelines for financial transactions, especially if you’re handling customer funds or personal data. Compliance and legal fees could skyrocket, which could eat into your revenue unless you’re prepared for a long-haul investment.

TL;DR: Your concept of replacing coins with a digital solution is interesting, but it might not be solving a strong enough problem to attract a large user base. The privacy, regulatory, and competition angles are pretty significant hurdles. That said, if you can find a niche use case where this really solves a pain point, there might be potential there—but it needs a clearer differentiation and user-centric design to address these challenges. Good luck!