apps I use to get the job done
There are plenty of apps that let you keep track of notes, many that sync across devices. By far, the best one out there is Evernote. Evernote lets you take notes in rich text or plain (my preference), include photos, links, tags and group things by notebook. It's very easy to quickly jot down something on a device for reference on another later. I don't use all of Evernote's expansive features, but for the simple note taking I do, it works very well.