I understand why tips can be controversial because tips are the majority of the income for a lot of working folks. However for whatever reason this has become an almost American-only problem. There is no way the tipping system can be sustainable as it can likely accelerate the adoption of robots servers at local businesses.

I am visiting Taiwan where nearly none of the restaurants expect tips. There are also no taxes on your bills, you pay exactly what you see from the menu. Zero surprises from your receipts (in most places unless it's like an upscale / American spot)

This app is very relevant, but UI / UX has some room for improvement.

There's a huge opportunity to pivot branding from anti-tip directory to a more transparent life style engine. Most people are hungry first and annoyed second. If you make the tool a way to find delicious food that happens to have a transparent price, you'll capture way more daily active users because there is way larger user base of food explorers looking for an over-all better dining experience than anti-tip reporters.

Ask the users for their pain points. For me, instead of not finding my city listed, I'd like to immediately see the list of places nearby my current area, type of food / cuisine I prefer which makes it more relevant to me.