Thanks for pointing this out - I couldn't figure out how to navigate Twitter to sort by date. If I was being paranoid I would have said that they picked up on an ad campaign we put out in 2015 to garner interest, however I suspect it is much more likely that the apps started around the same time and both happened to converge on the name Chowder (which is a fairly obvious choice for a food-app).

While I do think it's still fishy that they recently added some features which bare a great deal of resemblance to ours, that is a separate, unrelated issue.

As our app has been available for longer, I would hope that would be sufficient to at least protect ourselves in an infringement case - however rebranding might just be the most straight-forward option at this stage.