I bought Artemis long time ago, and I don't feel like the app was in development since then, in fact, it was losing features. I remember getting on top of the bus to show the frame wirelessly to my director, only to find out that the feature which was sending live view to his iPad was removed during one of the updates.
Artemis occupies the biggest amount of space in my iPhone, as all the shots in the app are kept in some poor format which is 10-20 times heavier than standard jpeg. 600 images are taking almost 2 gigs of space.
And then you can't use a standard sharing dialog from within the app, you first need to save a shot to your photo library, then switch to your photos and send it from there.
There are other things which can be improved (for example that slow 'running man' which appears between photo snaps is just killing me, steals too much time).
I really wish the company will tweak it to comply with modern standards. It was the first viewfinder which appeared on the market, but there are far better options now. It's easy to say that your application is used by cool guys, but were they happy with it? I personally used it on many award-winning films, including "Paradise" which won Venice Silver Lion and later was shortlisted for Oscar, but was I happy with it? Nope.
I paid around 25$ dollars back when I bought it (maybe more, maybe less, it was a long time ago), am I supposed to pay another 30$ now for something that will be abandoned next year? Doubt it.
Original 4K camera was nothing but close in size. BMC4K was actually closer to Red Epic than DSLR