The most annoying part of using my Apple Watch is having to enter the 4 digit passcode on the tiny screen multiple times day, for various reasons. Even if I have my iPhone, occasionally I still need to enter the 4 digit passcode. Apple needs to integrate a TouchID sensor into the watches crown. This way we can avoid ever having to enter a 4 digit code, except perhaps after initially powering on the device. Not sure if this has already been suggested but it dawned on me today so thought I'd share!