I've been using this in my emails:

<meta name="viewport" content="width=device-width, initial-scale=1.0">

But I notice that in a lot of examples and boilerplates the meta tag is listed as:

<meta name="viewport" content="width=device-width, initial-scale=1">

Are there any differences between the two? Will they render the same? Any client-specific issues?

Thanks.