What software do you use for in-app guides and tooltips?

At keypup.io we use Intercom. It's initially a chat tool (support, sales etc.) but they also have a whole bunch of in-app features, including what they call "product tours". They are really well designed and slick. Some limitations in terms of what you can show, how and where - especially if you start having lots of conditions attached to what you want to show and when, but other than that, pretty good tool - and super easy to create guides and tips too.