The ratio for Total World changes as the relative market cap changes. You can find the most recent breakdown on the fund's portfolio page.
As of December 31, 2018, the fund was 53.8% U.S.
Vanguard has a separate iPad app. They have for ages. And it is literally a separate app, "Vanguard for iPad", rather than a combined app.
I still don't know what snp is other than single nucleotide polymorphism. Google also suggested the Scottish National Party.