Y Combinator Co-founder Matching might be a bit more popular than Language.exchange. We know about 1 link to it since March 2021 and only 1 link to Language.exchange. 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.
I've had really great experiences on language.exchange, but it's not immediate - it takes a few tries to find a language partner who will work for you (shows up on time, compatible learning goals, etc.). 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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