keep in mind that the dev pretty much has to make a whole nother storyline, not just add a few missions or extra weapons so just be patient, episode two is coming out and its gonna rock a quote from the dev: "So how have sales been on iPhone? Eh. Let’s just say I’m hoping they’ll pick up when I release episode 2." well there u go, you can visit the devs homepage and check it out for urself he's been working on episode 2 since he released episode 1. and yes it is just one guy who made the game.
I guess that makes me feel better, but there clearly is a problem with dev's supporting games that they release. Instead of improving an already good product, they move on quickly to their next great idea...