A new HiSmart convertible messenger bag / Backpack has been recently developed that will vibrate if the phone starts ringing.
The HiSmart Pack, which was a combination backpack and messenger bag, with a waterproof canvas body and a leather strap, has the metal wheel embedded in the strap, which acts as a simple control system for your phone, the Verge reported.
If it is connected via Bluetooth and plug a microphone into the connected jack, the bag will vibrate when people will get a phone call, and they can answer it by pressing a button.
People will also be able to play and pause music, as well as do some very basic mapping. If the bag gets too far from your phone, it can buzz to remind you, and pressing a button will drop a pin on Google Maps, so people can do something like mark the place where they left their car and then look for it using a mobile app.
It's got 17 convenient pockets all over it, that could be flipped a few pieces around to turn it from a long-strapped messenger bag to a short-strapped backpack, and the electronics are tastefully low-key, people might not even notice them from a distance.