Your smartphone literally contains billions of transistors and other semiconductor elements. These can work as building blocks of digital electronic logic because of quantum mechanics – only quantum physics makes it possible to design the silicon-based materials in these integrated circuits to where they are now.
But your smartphone is not a quantum computer, yet – the data that are processed by these transistors are classical.
Also, your smartphone contains a digital camera with a CCD-sensor. This sensor is based on the photoelectric effect – which was explained by Albert Einstein by introducing quanta of light, photons, which got him the physics Nobel prize. The batteries of your smartphone are getting better based on detailed understanding of electrochemistry, including the quantum physics that is at the heart of understanding chemistry.
In future, your smartphone could do much more using modern quantum technologies – more precise navigation needs quantum sensor, physically secure communication can use quantum key distribution. Its batteries could be further improved using quantum simulation. And while quantum computers may stay quite big for a while, maybe you can at some point use their services through the internet, getting you better and smarter routes in congested traffic.