Yes, Google Pixel 2 has the Always-On display.
No. Google Pixel 2 does not have the normal 3.5 mm audio jack. You can use the USB Type C headphones or you can still use your 3.5 mm headphones with Google Pixel 2 with the help of USB Type C to 3.5 mm converter, which comes free in the box.
Google Pixel 2 has the latest Android 8.0.0 Oreo out-of-the box.
No. Google Pixel 2 is a single sim mobile phone.
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