I developed an iPad app for taking time-stamped notes while watching videos. It has other useful features like exporting notes to PDF and tagging individual notes for filtering them later. I developed it, having MOOC students being the primary target audience in mind, so I think Coursera students might find it useful.
Although there's no direct integration with Coursera platform, there are ways to get videos from Coursera into the app.
My question is: is it ok to somehow let other community members know about my app? (e.g. by making an announcement topic in 'Study Tips' subforum).