I question why you would want to shoot on an iPhone. Does it lend itself in some fundamental way to the story you are trying to tell, or would you do it just to say "shot on iphone"? I suspect that if you start with a great project, you'll find you've wasted it's potential, and if you start with a weak project you'll find you've wasted a lot of time.
In the end, I don't see a lot of opportunity to expand your horizons as a film maker unless it is simply to rise to the challenge. If that's the case, it's like gouging your eyes out to challenge yourself. You won't necessarily do anything better, but you may accomplish the same thing with a severe handicap.
you gotta' understand,i am going to use a pocket recorder to learn distancing,lighting & practice editing etc......when i feel i am proficient with fcpe & video recording i am going to make an excellent project film with the canon 814 az i just purchased on ebay....yahoo......
fyi.....i have decided on the kodak zi8 with the lens mod to add filters:wide view,polar,uv,etc {not an iphone}........it will be mounted beside my sony pcm-d50,which will most likely be useless in most outdoor shoots but pretty decent inside.......i have a blimp,though...
my screenwriting is going great.....i wrote a short story the other day about a 5 year old boy who hears a scratching under the sidewalk while he is drawing chalk pictures on it.....he hears the scratching for months,but his grandpa can't hear it...one day a locust comes up from a hole it dug through the sidewalk..{yes,a locust can bore a hole in 3" slate}i witnessed it when i was 5......my grandpa said"you got good ears,boy".......the short is called......"THE SCRATCHER".......these are memory's more than screenplays.they're organic & true & to the point.perfect,i think for super 8mm{for now}.....
then i wrote another short about the time my grandpa tricked me into digging up his apple tree by saying i would be digging a swimming pool..........at least he let me fill the hole full of water & play in it until the end of summer........there's a pineapple grenade in that story...
then,i wrote another short about the time i took my star wars at-at outside in december & left it out overnite which is when the blizzard of 78 came......i went out the next day to dig for it & ended up finding a 1200 year old native american canoe anchor which i sold to an antique dealer{i should have kept it}....that story is called"WHERE'S THE AT-AT AT".......all story's from when i was 5....
i feel gear is secondary,,,,,ATTITUDE & VISION are primary.........i know,i talk too much.....