People often get scammed when they're travelling abroad. I think this is largely an awareness problem. When one is travelling to a new destination, one expects that due to cultural differences, some unexpected/different things will happen. So, one is more suceptible to scams. 

However, if one was aware of the kinds of tricks scammers at any given location tend to use, one would be much less likely to fall for the scam. At the moment, this awareness is somewhat difficult to obtain. You can go online and search "common scams in new delhi" but the information is often outdated. It is also spread across a lot of different websites and formats, which makes it cumbersome to review. One cannot also easily assess which ones are common scams (and thus which ones you need to be more careful about). 

So, if there was a dedicated platform that curates information about scams would be very useful. As per this quora thread, it seems like this is something a lot of people want, but which just doesn't exist. Some features I have in mind:

1. Each scam is its own article. People can mark if they have also experienced it and comment with further opinions.
2. Similar scams are merged together. 
3. Scams are ranked by the recency and frequency. 
4. Allow me to input my travel plans. Then as I approach the date, send me an email telling me what scams I might be likely to encounter on any given day.

To start off, you can focus on just one popular destination. You can then create a bot that automatically scrapes information from Reddit, Quora, Tripadvisor blogs, and other webpages that rank highly on the search engines. You can also visit some popular tourist destinations and ask the tourists in person. Then, with a little bit of advertising on travel communities and subreddits, this platform should easily take off. People are generally more than happy to share their experience of getting scammed so others can be more aware. 

Monetization channels: You could make it a website people can pay a small fee to access. You could partner up with Tripadvisor or Expedia or other popular all-in-one travel planning websites, who would probably be happy to pay you for the data. You might also be able to get funding from police agencies (who also want to crack down on scams) but this is less likely.

There's also scope to make this a broader general scam alert system – something that even locals could use.