Years ago, I was obsessed with the fact that journalists focus on kit quality over content quality when it comes to doing multimedia work. Nothing I've done in the last couple of years has suggested to me that this has become any better as an issue. The quality you can get out of your mobile phone is astonishing compared to what mid-range dedicated cameras were doing a decade ago. Concentrate on doing great work with your phone, and upgrade when you hit its limitations.
And when I say "concentrate", think about how you can do better work with it.
Here's a wonderful example from Apple of what the iPhone can achieve when used cleverly:
What's even more interesting is that there's a behind the scenes video showing how it was all done:
Now there's some serious kit in there - some of it to allow it all to be shot in one day, yet directed by one guy (Jake Scott - the son of Ridley Scott, who directed the first ever Mac ad, fact fans). But the majority of it is just dedicated to helping keep the phone more steady - or to allow it to move more smoothly. You can get a bunch of the way there with just a Glif and a GorillaPod. But there's also hand-holding, but thoughtful, two-handed hand-holding.
For a touch more inspiration, they've also done a behind the scenes on a Burberry fashion show captured with an iPhone 5s:
Stop worrying about the kit. It's all about the content quality.