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Nearly 500 smartphone brands have left the market since 2017
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This is a most excellent place for technology news and articles.
I don't. Having it under the screen like Pixels makes it possible to unlock the device without picking it up.
I take my phone out of my pocket and unlock it more often than I unlock it and leave it on a table, so the back makes way more sense
Put your hand in your pocket, take your phone out, and it's already unlocked by the time you look at it
That said, why not both? It's not that expensive of a component. Cameras cost far more and we're fine having 3-5 of them on devices now.
In my experience (having used Pixel 7 nonpro for a while) it doesn't always pick up your finger. Side-mounted (power button) sensor is the nice compromise imho