Plus legal fees, salaries of everyone at the office (which is a bit more than app development costs when you think of all the middle and upper managers involved), leasing office space itself (and other related costs), assuming they haven’t gone full remote. Marketing, lobbying (at national, regional, and local levels, since individual cities decide whether or not to allow them at this point), PR, finances, paying the team that convinces the investors to throw more money at it instead of pulling the plug (though I bet sunk cost fallacy does a lot of legwork for them).