Evernote is an organizer that lets you put your notes, to-do lists, outlines, photos, and web "clips" into notebooks. If you're writing down your family history, organizing your recipes, planning a vacation, or just jotting down your thoughts, Evernote is an invaluable tool for your memory. Don't worry about saving -- everything you put into Evernote is uploaded automatically into your Evernote account "in the cloud."
What really makes Evernote great, though, is that it runs on everything -- PCs, Macs, iPads and iPhones, Android tablets and smartphones, Kindle Fires and Chromebooks. You can make your notes on one platform, and refer to them on another. I use it to jot down ideas on my iPad that I can refer to from my PC at work (and vice versa). My grocery list is on it, because that means it's on my iPhone too, and when I see something interesting that I want to look up, I'll take a picture with my iPhone in Evernote and jot down any details, then look it up on my PC or iPad. You can even share your specific notebooks with other Evernote users -- great for planning the family vacation or a church event with others.
While Evernote does have a Premium level and also offers in-app purchases for advanced features, the free level probably will do everything that you want. You'll find lots of things to do with it, and you'll wonder how you ever lived without it.