Paper prototyping: how TenTune tested an app with pencil and paper

Good summary of the steps and tools to launch a new product from Tristan Kromer

Paper Prototyping: How TenTune Validated an App with Pencil and Paper

Tristan Kromer tells how the founders of TenTune, a music discovery app, tested their idea in a coffee shop with hand-drawn screens and an MP3 player, before writing any code. In one day, ten people showed that ten seconds are enough to judge a song, a lesson that coded tests would have taken a month to deliver. The rule: test the riskiest assumption first, with the lowest-fidelity prototype possible.

Source: Tristan Kromer (Grasshopper Herder)