Which file do I add meta tags too?

Hi there,

I need to add the following to the header:

<meta name="viewport" content="user-scalable=no, width=device-width, initial-scale=1.0" />
<meta name="apple-mobile-web-app-capable" content="yes" />

but not sure which file I add this too. Or would I add it via functions.php?

Any suggestions would be great, thanks!