Taschen: Concept and realization of a mobile app (iPhone, Android) of „Keel’s Simple Diary“

Taschen | 2013 | Keel's Simple Diary


It was necessary to develop a mobile app for the successful book “Keel’s Simple Diary” published by Philipp Keel at TASCHEN. The app should reflect the diary’s simplicity and stay true to its roots of success. At the same time it should utilize the potential a digital diary app can offer.

Our work

Based on the form of the book “Keel’s Simple Diary” we developed ideas how Philipp Keel’s established diary, which is structured by several questions, can be augmented by the possibilities of a smartphone-based app. The implementation of a native app offers the potential to take additional pictures and link them to each diary entry. Likewise, location data or persons from the contact list, who you spent the day with, can also be linked with an entry. Events, therefore, can be easily accessed in several ways because they can be sorted after persons and locations.

For the best possible viral distribution, we came up with a free version of the app, which does not contain any restrictions on use but only offers a limited set of questions from the book. The full version is easily accessible via the In-App-Purchases we accordingly integrated. Users, therefore, are able to test and share the app without having to blindly buy the full version.

We translated the concept into wireframes and arranged the designs according to the book and close considerations by the author Philipp Keel. We implemented the app natively for iOS and Android.


Even without concentrated marketing actions the desired concept of an optimal viral distribution via a free trial version, that can be upgraded, had taken place. Within a short amount of time, Keel’s Simple Diary App has found a large user basis, of which a high percentage has upgraded to the full version.

Keel’s Simple Diary – mobile App

Keel’s Simple Diary – Website

Keel’s Simple Diary – Website