I'd like to have a gesture in js, where you can tap multiple times with two fingers and get a result that shows your action. It works perfectly fine if you set the attribute pointers to 1 (tap with 1 finger) or if you remove requireFailure().
You can test the code over here, tapping with two fingers works on your smartphone or an emulator: http://codepen.io/JanIngwer/pen/eNwOPO
mc.add(new Hammer.Tap({ event: 'tripletap', taps: 3, interval: 800, posThreshold: 100, pointers: 2 }));
mc.add(new Hammer.Tap({ event: 'doubletap', taps: 2, interval: 800, posThreshold: 100, pointers: 2 }));
mc.add(new Hammer.Tap({ event: 'singletap', interval: 800, posThreshold: 100, pointers: 2}));
mc.get('tripletap').recognizeWith(['doubletap', 'singletap']);
mc.get('doubletap').recognizeWith('singletap');
mc.get('doubletap').requireFailure('tripletap');
mc.get('singletap').requireFailure(['tripletap', 'doubletap']);