Having only a mobile web version isn't necessarily obsolete.

The current demand for native apps on mobile devices stems from the fact that it is easier to get high quality user experience on the native apps than on mobile web browsers. This was true of desktop apps, too, 5-10 years ago. However, web-apps offer a host of other advantages and so long the UX can be brought up to a decent quality, I'd take a mobile web-app over a native app that I have to go find and install for the same reasons I prefer web apps to desktop apps (both to use and to create).

So, 37s's decision to do a mobile web-app is either obsolete or visionary. I'd bet on the latter.