It’s a common problem: You have Microsoft Outlook at work, a different e-mail program at home, and a smartphone in your pocket, all with independent inboxes and outboxes. Ideally, all your devices should communicate, so that when you receive or reply to a message on one, it’s reflected on all of them. But they don’t do that.

Wise question. I wish I had asked it before leaving my phone and two years’ worth of numbers in a taxi. Fortunately, backup systems abound. If you go through cellphones like toilet paper, try the Universal Pro kit ($80; datapilot.com). It includes cables that let you transfer data to your computer from just about any phone, and it syncs with Microsoft Outlook.