Moto's Z series have a clever interface that is a combination of several tiny gold contacts and magnets that allow modules, or 'mods' to simply click on to the back of the phone. The design makes it absolutely fool proof that you will always get it connected right, and the magnets hold the mod on tight enough that it won't fall off, but not so strong that it can't be easily removed.
There are few different mods that are simply louder speakers, for instance, JBL has a Moto Mod that not only adds a louder speaker, but a speakerphone, a kickstand, and an additional battery.
Or there's this cool Moto Mod that is actually a projector!
How about a game pad?
Or a camera with a zoom lens?
There are several more mods available, including cases, batteries, or 360 degree cameras. The cool thing is that Lenovo has settled on this standard interface, so even though you'll upgrade to a newer Z phone in a couple of years, all of your mods will still work.
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