Train yourself to recognise notes within a major scale with regards to their position in that scale. This is called "relative pitch" (not the same as Perfect Pitch) and can be learnt by anyone with enough practise. Hear the note (you will need sound on, obvs) and select the correct note on the keyboard. When your accuracy is at 80% or higher, the next level is unlocked. TO DO: add in stats and practise mode for tricky notes.
Inspired by the "Functional Ear Trainer" mobile app by Serhii Korchan Code & concept: giocosso