US research company ComScore says American smartphone owners are now spending a lot more time on mobile photo sharing service Instagram than Twitter.
Twitter still gets a lot more visits - a function of the fact it has around 29 million US users compared to around 22 million for Instagram (our of roughly 110 million smartphone users in the country).
But people are spending a lot more time on Instagram, and the photo-sharing site has more daily active users (DAUs).
These figures are for August 2012. Click graphic to enlarge:
Source: ComScore.com