TIL there are surplus food apps that can save you big money on groceries

• Too Good to Go
• Flashfood, where you can order groceries nearing their best by dates for up to 50% off, then pick them up in local supermarkets
• Misfits Market
• Olio

Source

Note: I haven't used any of these, I can't speak for them. I do think it's cool for the environment and people on a budget though.