For a bit of context, a web-based app doesn’t embed or include the font files in the app itself; they are not a part of the final build. Instead, the fonts are called via @font-face and wouldn’t display unless the user was connected to the Internet. Use of the fonts is also restricted to hand-held devices running mobile operating systems.
With that in mind, a web-based app is covered by the webfont license and pageview tallies apply instead of something like sales or downloads. It should be noted that all webfont license restrictions, like the ability to serve only WOFF and EOT font files, are still applicable.