Mobile browsers/devices handle client certs better than any desktop I've seen. Especially since they have hw trusted storage. The issue is identity/linkage.

Mobile browsers/devices handle client certs better than any desktop I've seen. Especially since they have hw trusted storage. The issue is identity/linkage. If they let you set up an arbitrary number of keys, so you could do one per site, that's fine (and really, if you use the same username everywhere it's sort of the same thing)