I do not audit code line by line, bit by bit. However, I do due diligence in making sure that the code is from reputable sources, see what other users report, I’ll do a search for any unresolved issues et al. I can code on a very basic level, but I do not possess the intelligence to audit a particular app’s code. Beyond my ‘due diligence’ I rely on the generosity of others who are more intelligent than and can spot problems.