Jacob says that the biggest challenge for the app was coding the gesture-based interactions.
"Initially the gestures were far more advanced," he says, "tracking the exact movement of the fingers. [I found this] far too unreliable and hard."
While many users have tweeted about how much they love the design of Sun, Jakob's the first to admit it's not perfect.
"I didn't nail it one hundred percent," he says. "Many users don't realise you can pinch in to reveal a 10-day forecast or pinch out to get a overview of all cities. I removed the tutorial from the first version, as I it simply wasn't elegant. Adding a tutorial is easy, but lazy - so I'll have to find some natural signifiers [in a future version]."
This isn't likely to happen any time soon though, as Jakob has just landed a job at a studio in central Copenhagen.
"That, school and complaining about the weather is pretty time consuming," he says, "so I don't know when I'll find the time to improve Sun."
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