According to comments from a Google engineer, found by XDA Developers, the Google Pixel 4 will have much more useful dual-SIM functionality. What this means specifically is that - much like the latest iPhones - you'll be able to use both a physical SIM and the in-device eSIM for two separate carriers simultaneously. 

This is news for Pixel because, while some regions' Pixel 3 models have eSIM capabilities as well as the physical SIM tray, you're made to choose between them.

You can't have both of them active. So if you have two accounts, for work and personal, you can't have them both active and useable on a single Pixel. Or rather, you can have them active, but you can only use one of them for calls/texts, so it's as good as only having a single active SIM. 

These comments from the engineer, posted to a Google project open source forum thread, suggest this is being fixed for the next major flagship Android phones from the search giant. 

While dual-SIM hasn't always been seen as a necessary feature, it's seen something of a resurgence in recent years with many manufacturers including it as standard in many of their devices.

With that - in addition to the option given by many Android manufacturers to clone secondary versions of apps for separate accounts - the need to carry around two devices for work and personal is lessening. 

As for the Pixel 4, little has been rumoured about it so far. Most recent rumours have focussed on a nearing release for the more affordable, "lite" versions of the Pixel 3

Google's main Pixel launches tend to happen later in the year, towards the end of autumn. The only thing we can be sure of is that these new devices will launch running the latest version of Android, which will be Android 10.0 "Q" by the time they're announced.