By default, Android apps should function so that the status bar should be resized to be as tall as the notch, and app content should be display below that. One of them is that there will be no more than two cutouts on a device and another is that there will be no cutout on the left or right long edge of the device. In the blog post posted by Megan Potoski, Product Manager, Android System UI, highlights that Google is working with device manufacturers to mandate a few requirements. And with Android P being created to support the notch, Google is basically giving Android phone makers an incentive to come out with more notched phones.
That said, Google has now stated that while it is fine to have one or even two display cutouts in Android devices, having more than that is definitely not permitted.
This means giving app creators the tools to develop for phones with multiple notches (a top and a bottom, for example) and notches in different sizes and locations.
She goes on to encourage to developers to test all screens and versions of their app experience to make sure they don't get buggy on devices with notches.
"In portrait orientation with no special flags set, the status bar must extend to at least the height of the cutout". There are some who feel it is too distracting, asymmetrical and spoils the overall aesthetics of the device while others who are not too bothered by it.
"A single edge can contain at most one cutout", it stipulates on its Android developer pages, adding that "a device cannot have more than two cutouts", and "cannot have cutouts on either of its longer edges".
A handful of Android Oreo phones that have a notch, usually at the middle of the top of the screen, include Android co-founder Andy Rubin's first and last Essential phone, the PH-1, the Huawei P20, the popular OnePlus 6, Asus's ZenFone 5, Oppo R15 Pro, and Xiaomi's new Redmi 6 Pro.