Instagram has become a phenomenon among iPhone users over the last few months. The photo-sharing app, which amassed 100,000 registrations in its first week, has now about 2 million registered users and around 290,000 photos are uploaded by them daily.

Now, where users go, brands tend to quickly follow. For brands, the iPhone-only app’s highly usable interface offers another quick, easy way to generate and share visual content with existing fans and, thanks to Instagram’s search and browse functions, attract new ones.

Instagram first conveyed its interest in welcoming brands when the startup partnered with several brands including Charity:Water, Brisk Iced Tea and NPR to introduce a new hashtags feature in January,.

Charity:Water has asked users to raise awareness by tagging images of water with the hashtag #charitywater, and NPR is challenging followers to capture #love or #hate in an original photo.

Brisk Iced Tea, a division of Pepsico, has gone a step further by inviting fans to tag their photos with #briskpic for a chance to be featured on a can that will be unveiled at the SXSW conference this month.

Marketers from the above-mentioned companies agreed that there is no single approach for brands to take on Instagram. “Just get started and don’t be afraid to share photos and see what your followers say about them,” advises Josh Riedel, Instagram’s manager of community and partnerships.