I think Calendar 5 is kind of the paid version (7.99 euro) of Calendars which is free with loads of in-app options and lack of a few features if you don't do in-app). Although also Calendar 5 has a few optional in-app purchases.
I tried loads of different calendars but I always got back to Week Calendar.
I love and use Week Calendar app (iPhone, iPad) on my iOS devices especially the way that it shows my Google Calendar from both me and my wife and especially the option to see the travel time in minutes to an appointment either from home or your current location. The only feature it lacks is showing that same travel time in the widget for people such as me who are using Google Calendar as a source. It's also annoying when you first start to use the app that they charge for the iPad and iPhone separately. You can also do other in-app purchases but you don't need those. I also didn't install those.
