Android/iOS: Updating your contacts every time your friends change their info can be annoying, especially if you don't know they have changed it. Addappt, on the other hand, is a social contacts app that updates automatically.

iOS: When it first launched, Cobook was one our favourite address book apps for iOS. Development eventually stopped when it was purchased by FullContact. Now, it's back, and it works very similarly to the original app.

You have a lot of options for address books on the iPhone, but we like Contacts+ for being a solid option without a lot of bloat. It has heaps of features without being too overbearing or difficult to use.

If you're looking for a smarter way to manage your contacts, Contacts+ for Android is your best option. It brings a number of features to the table that help you quickly get in touch with your contacts and keep up to date with them.

Fruux is a great way to synchronise contacts, calendars and to-dos across devices, but now the service wants to give you a unified place to manage all of that data as well as keeping it up to date on every screen you use. The new Fruux web editor makes it easy to update contact details and keep everyone organised.

iOS: Contacts+ syncs information from all of your connected services to give you complete contact cards for your friends, organised with big photos of each person. One tap calls them, another gets you up to speed on what they've been doing lately.

It's hard to get by these days with just one email address. If you want to sync your contacts between all your email accounts, it's actually very easy to do with a free tool called Soocial. Here's how.

Every time you go to type an email address into the iOS Mail app, you get a giant list of everyone you've ever contacted that might fit the letters you've typed. This can get annoying very quickly. Here's how to delete those from your phone for good.

iOS: Cobook is a smart address book that combines your default list of contacts with Facebook, Twitter and LinkedIn data. It provides you with all the information you want to have in an address book without cluttering up the interface.

We often find contact information in the body or signature of an email, but we neglect to add it to our contacts and are forced to search our emails for a phone number or address later on. Morse takes care of that problem by pulling contact information stored in your emails and adding them to your address book automatically.

It's increasingly rare that you ever need a friend's physical address anymore, but there are occasions where you need to send out a physical letter. If you don't feel like emailing, calling or posting a Facebook update to track down addresses, Postable is a dead simple and secure address book where your friends can enter their own info.

iOS: Buzz Contacts replaces your iPhone's contacts app with a contacts manager and dialler that's easy to navigate, offers partial name and number search, lets you quickly SMS or call your contacts, organise your contacts by list and category, and looks good in the process.

Oddly enough, there aren't too many contact management tools for Android that aren't also dialler replacements, or focused entirely on replacing whatever built-in tool you have on your device already. We have to agree with our iOS counterparts on this one -- Smartr by Xobni is the best address book for Android, if you're looking for a contact manager that actually makes it easier to find and interact with the people you need to talk to.

There are piles of address book alternatives for the iPhone, but after digging through them all, we settled on Smartr Contacts as your best bet. It gives your contacts an upgrade by adding a historical overview of your interaction and adds social media updates to their pages. Overall, your address becomes much more useful.

Mac OS X has a great built-in address book and a number of useful third-party alternatives, but out of all the options Cobook is our favourite. It's a very new app, currently still in beta, but its intelligent search and social media integration make it very easy to love.