This counts one install per 12 month period, whether update or fresh install (new user). So it’s €0.50 per user device. For application providers that opt into the new terms and release updates every two weeks like clockwork even if there are no meaningful updates for 300Mb application bundles (Facebook, Duolingo, a few others)…this is likely a fair cost (and my suspicion is that yes, there's a premium, but it's probably not Apple's usual 20%+ premium on products since many applications would not be subject to this fee at all, even under the new terms).