Y Combinator Co-founder Matching might be a bit more popular than Polyglot Club. We know about 1 link to it since March 2021 and only 1 link to Polyglot Club. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
Polyglot Club Official Website - Practice languages and find friends. Source: over 1 year ago
One idea I just remembered is to find a business co-founder that already knows a market well and sees an opportunity. Startup School's co-founder matching service is quite good. Source: almost 3 years ago
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