I like how this app can help to know who calls me at my current location without having go out in public for it! It's very handy when i'm working remotely because sometimes people call but they don't have their mobile devices with them so we could be missing an important contact/client etc.
Sometimes there might also appear some delays before getting answer during peak hours especially if its between 3pm - 5am since most likely everyone will sleep then which may cause issues regarding time keeping track while doing work outside office environment. But other times once someone answers he would be able reply within seconds unlike earlier where response was delayed up until 20 mins after first answering. This helps solve problems such as "whoever just left no message" problem.