https://open-gpt.app/ VS TCGJoin

TCGJoin's answer:

Two overlapping groups.

The core audience is collectors who have accumulated more cards than they can track by memory typically returning players who came back to Pokémon or Magic as adults, plus long-time collectors finishing sets. They want to know what they own, what it's worth, and what's missing. Mostly 20–45, Europe first (Spain and the UK are the strongest markets today), with the app published in 8 languages.

The second group is competitive and casual players who use the deck builder to test lists against what's already in their binder before spending money.

Local game stores sit alongside both: they use TCGJoin as a reference their customers can trust, rather than as a sales channel.

TCGJoin's answer:

Most card apps are built around a single game. TCGJoin is built around the collector. One account covers 10 trading card games Pokémon, Magic: The Gathering, One Piece, Yu-Gi-Oh!, Lorcana, Dragon Ball, Digimon, Naruto Kayou, Riftbound and football stickers so your whole collection lives in one place instead of five separate apps.

The AI scanner does the heavy part: point your camera at a card and it identifies not just the card but the exact variant set, language, edition, holo treatment which is where most of the value difference actually sits. From there you get live valuation, set completion progress, and an AI deck builder that checks your list against the current format rules using cards you already own.

Everything is available in 8 languages, and prices are shown openly rather than hidden behind a listing.

TCGJoin's answer:

Three reasons.

It's collection-first, not marketplace-first. Many tools exist to sell you cards, so the price you see is the price someone wants you to pay. TCGJoin starts from what you own and what it's actually worth you can use it for years without buying or selling anything.

Variant-level accuracy. Knowing you own "a Charizard" is useless. Knowing which print, which language, which edition is the entire difference between a €3 card and a €300 one. That's what the scanner is built to resolve.

One app instead of five. If you play or collect more than one game and most people do now you stop juggling a Pokémon app, a Magic app and a spreadsheet.

TCGJoin's answer:

TCGJoin started from a pretty ordinary frustration: card prices are opaque, and that opacity is profitable for everyone except the collector. Values swing on hype, listings are inconsistent, and a beginner has no realistic way to tell whether the card in their hand is worth €2 or €200 which is exactly the gap speculation lives in.

The first version was a scanner built to answer one question honestly: what is this card, precisely, and what is it worth right now? Collectors kept asking for the next game, and the next, until it made more sense to build one platform covering every major TCG than to keep building separate apps.

The goal hasn't changed: give collectors the same information the people setting the prices already have.

TCGJoin's answer:

The backend runs on NestJS with TypeScript, following a clean architecture with CQRS, backed by a relational database holding the full card catalogue sets, variants and pricing history across all supported games. The frontend is React with TypeScript, server-rendered for SEO across the 8 published locales. Card recognition uses computer vision models for detection and matching, with a variant-resolution layer on top. Everything runs on cloud infrastructure with automated CI/CD and monitoring.

TCGJoin's answer:

Spanish TCG gamers