No, it does fine with screens. The problem you're encountering is that we don't have any Google Fonts in the MyFonts library currently. The app can only return fonts that we have on MyFonts.
MyFonts is my go-to source for fonts when I'm doing design work, and I understand why WTF is limited to MyFonts' database, but I do think it kind of cripples it and it would be really cool if it could identify external fonts by name but suggest a similar font in the catalog. Thanks for the great service you provide!
MyFonts is one of the best font sites I know of, with a huge selection of fonts and top designers. There are regular offers on new fonts, and informative interviews (great for discovering typefaces).
I find WTF very useful. Sure, it's not perfect, and I continue to hope for better accuracy and results. I'm glad to hear they're working on it.
"Useless" is a bit strong, but the comment emphasizes the tool's most important limitation.
I might've said "Since WhatTheFont doesn't include fonts typically used on web sites, this tool is radically more effective when identifying fonts used in printed materials."
I'd like to understand if the team considers this to be a problem that they plan to solve, or if WhatTheFont will only identify fonts that they can monetize. (No judgement either way.)