Join us !

Applidium is a tech startup based in Paris. We're behind many successful mobile apps, and we're busy creating the next mobile blockbusters.

Technical challenges

In order to show us your skills in a different way than in your well-presented résumé, the Applidium team offers you 4 mini-challenges.

Whether you are curious, motivated, creative, or just feel inspired by these challenges, don't hesitate to send your solution suggestions as well as your application to We will be thrilled to talk them over during an interview.

You can choose any programming language you wish, and of course there's no need to solve everything: a partial answer will already be interesting!

Challenge #1

Which Restaurant to choose?

The neighborhood around our office is full of small restaurants, each one as nice as the next, which makes the daily choice much too hard! Could you help us create a weekly "restaurant" agenda, according to the optimal calorie intake for our body? Needless to say, we'd rather not go twice in the same restaurant during the same week.

Your program will read the number of weekly calories to eat from its standard input, followed by the list of available dishes and their respective calorie values (in kcal), in the following format:

"Didier's Kebab" = 8800
"Vegetable plate from 'chez les filles'" = 12
"BigMac" = 323
"Asian noodles dish" = 281

Your program will write a planning to its standard output, for example in the following format:

Monday: "Didier's Kebab"
Tuesday: "BigMac"
Total: 810 kcal, out of 8392 kcal required

Challenge #2

AppStore Rankings

Quite often we need to know the AppStore ranking of one of our applications.

Could you write a program reading an application's name from its standard input and writing the app's ranking to its standard output?

Challenge #3

Wall of Application Icons

In our office, we display on a TV screen a mosaic of our most downloaded apps in the AppStore. To prevent stuck pixels, it is important to shuffle the icons from time to time. Could you write a program that reads a list of applications from its standard input and writes the same list randomly shuffled to its standard output while ensuring that every application icon has changed position?

Each application will be represented by an integer, in the input as well as in the output:

echo "1,3,2,5,4" | ./appliWall => "3,1,4,2,5"

Challenge #4

Retina Display

The iPhone 4 has a screen resolution which is exactly 4 time greater than the one of previous iPhone models. Even if it enables a much sharper display, it is also necessary to update the different Bitmap images used in the applications.

Do you have an idea to make this process automatic ? For example, this would consist in creating a 64x64 pixel image as nice as possible from a 32x32 pixel version.