Not very pleasant. I have multiple google accounts setup on my device and just like gmail app lets you to swtich between different accounts unfortunately google calendar does NOT allow you to do it. It has single pane of view whether you select one or all or two calenders but the view is single which makes your calendar extremely clogged and confusing. I think it would be a handy feature to introduce in google calendar to be able to switch views just like google mail (gmail) app.