I saw this app and thought it looked interesting, good way to work these things out.  In all countries they all have different levels of tip and it's not always clear how much you should tip.  For people that have been to the US before you know you should tip for everything, and in some places they even give a few options and they expect the tips, where as some where like Japan this can be seen as rude to tip.

I reached out to the developers to ask what inspired the idea, it was to cover a niche that told you the tipping culture, but not only that it can work out the tips recommended on what you thought of the service, the group size and the total amount on the bill, they thought it might help people in terms of adjusting to cultural expectations when tipping is concerned.  It also works out the bill from the group so you can all know how much everyone needs to pay.

Plus they were interested in the journey of creating an app, designing it and developing it and then the process of getting it launched.  So this was the perfect app to start off with.

So far on iTunes the feedback is very positive reviews, all 5 star.  There are plans to continually improve and develop the application, the plans are to angle this towards being a travel app too and there has been a recent addition to added a mini travel guide to each country. This will be improved upon as time goes on to be more comprehensive. 

They also have ideas to link up with restaurants, bars etc to offer bespoke discounts when the app is shown at the till. 

A suggestion from me  would to be able to upload a review to TripAdvisor from inside the app as well, perhaps as a paid add in.

You can read all about the app from their website, you can also follow these the links to download the app from the App Store, Amazon Store or the Google Play Store.  There are some screen shots at the bottom.