A good smartphone is really a mini-computer in your pocket, capable of doings things that computers even five years ago could not do.  But you’re not getting the most out of your smartphone if you’re just using it for making calls, checking email, and surfing the web.  Those are all good things to do, but if you really want to take advantage of your smartphone you need to learn how to use your apps.

What is an app?  Simply put, it’s a mini-application.  You use applications all the time: Microsoft Word is an application, so is Powerpoint, so is your mail program.  Traditionally, applications are big complicated pieces of software that can cost hundreds of dollars. But Apple pioneered the idea of an application as an “app,” a high-powered but simple application that you can get for free or purchase for a relatively small amount.   Some apps are simply smartphone versions of websites or programs that you can use on your computer, while others were created simply to use the power of your smartphone in interesting ways.

What follows is a very unofficial, incomplete, and totally personal Guide to some of the best apps out there for the iPhone and Droid smartphones.  There are hundreds of thousands of them out there, and lots of places where you can get advice about what to buy, but these are the apps I use all the time.  Amazingly, the Android operating system for Droid phones has caught up with the iOS operating system for iPhone, and almost all major apps are available on both platforms.  I also included iPad apps that are specifically designed for the iPad.  I did not include Blackberry apps, because I have not used them and the Blackberry is still very far behind in establishing its app sales.

You can find iPhone and iPad apps at the  App Store, and Droid apps at the Android Market. Just search for the name and you’ll find them.  This is a work in progress, so if you have suggestions of new apps to add to the list, just email me.

Here is an outline of the organization for the apps that follow

• Business and Productivity Apps
• Communication Apps
• Information and Reference Apps
• Leisure Apps
• Entertainment Apps

BUSINESS APPS: Productivity, Social Media

Google (iPhone, iPad, Droid) (free)
The Google app is a must, if only because it gives you quick access to the Google sites you might be using, like Docs, Calendar, etc. Unfortunately, Google does not have dedicated apps for most of its services, so this is the collective “hub” for getting to them without going through Safari.
You can also do a search through the app. Just convenient to have it directly.

Google Voice (iPhone, GV Connect for iPad, Droid) (free or $1)
If you don’t use Google Voice at all, you should check it out.  You can set up a universal phone number that will ring all your phones (i.e., mobile, work, home office) at once, so people can call you at one number and get you wherever you are.  And then Voice can also transcribe your voicemail (although the transcriptions are not great) and save it as an audio file link that you can access with a click.  If you use Visual Voicemail that comes with the iPhone, this is a slight upgrade.  Also great because your text messages are all available on Google Voice wherever you are (any internet computer, and your phone), which can be helpful. For the iPad, Google doesn’t have a dedicated iPad app for Google Voice, but you can buy GV Connect that provides a good app experience to review your messages and texts.

Evernote (iPhone, iPad, Droid) (free)
A terrific notetaking app that can sync your notes between your mobile device, computer, and any other device, accessible anywhere you can get on the internet.

Social Media Apps (iPhone, some on iPad, Droid) (mostly free)
All the big social media sites have apps for your smartphone that are very useful and often better than the computer experience: Facebook, Twitter, Linkedin Foursquare. They’re all free, and what’s great about them is your ability to check out social media updates in your downtime, without interrupting productive work. For example, surfing social media is a fun and easy thing to do when you’re waiting on line, which turns out to be a lot of my day. Not all of the sites are on the iPad with apps (no Facebook app?), but they all have third-party services that let you check out your social media fees (fyi, the best Facebook iPad app is Facely HD).

Dragon Dictation (iPhone, iPad) (free)
People that don’t type well will love Dragon Dictation, a free app that will transcribe what you say into it, turn it into text, and allow you to save it as a note or send by email.  Very effective, and pretty good with transcription.

WordPress (iPhone, iPad, Droid) (free)
Wordpress has a dedicated app for reviewing your WordPress blogs.  You won’t want to write a blog post, but you can review comments, approve them, do some little things.

Real Estate Search Apps (iPhone, some iPad) (free)
The real estate search apps are all pretty good and free.  The best smartphone  are Realtor.com’s and Trulia.  Great for searching on maps, so you can see where the properties are. The best iPad app available right now is Zillow, which I don’t love (seems like the inventory is incomplete) but does provide a big screen experience for home browsing on the iPad.

DropBox (iPhone, iPad, Droid) (free for 2GB storage)
DropBox is an amazing app that allows you to store your big files so you can share them between computers, and now between your mobile devices.  Great way to move big files from one computer to another (like, from work to home), or to keep them available wherever you are.  You can also share files by putting them into a public folder, and sending people the link, which is better than emailing them that 10MB PDF.  It’s a great service, and the apps are terrific. Perfect for moving movie and picture files from computer to computer, and then having access from your smartphone.

COMMUNICATION APPS: Messaging, Calling

FaceTime (on iPhone, $1 app for iPad)
Facetime is not strictly an “app,” because it comes on the iPhone 4 standard and can be found when you pull up a contact, but you should make sure you know how to find it. When you pull up a contact in your phone, you can  click on the number to call the number, the email to email the contact, but at the bottom of the contact are buttons for text message and facetime.  For iPad, you can get an app for about a dollar that works great.  Remember Facetime only works when you’re on a wireless network.  (I don’t know that Droid has anything similar.)

Speed Dial (iPhone) ($1)
A must for the iPhone, which does not have dedicated buttons for speed dials.  There are lots of variations on this.  You can get a free app called “Speed Dial #1,” “Speed Dial #2”, and so on, which gives you a dedicated button for a one-touch dial, but you’ll have to memorize the order.  A better choice is “Speed Dial,” which provides a yellowish version if iPhone’s “Phone” app and leads you to up to 24 programmable buttons that you can label for your speed dials.  Takes about 10 minutes to set up, and then you have two-touch speed dialing: hit Speed Dial, then hit the name you want. Very quick.

Meebo (iPhone, Droid) or Imo.Im (iPad, Droid) (free)
If you use computer-based instant messaging (as opposed to text messaging on your phone number) on services like MSN, Yahoo Messenger, Facebook messenger, Google Chat, or lots of others, you can consolidate all of them on Meebo on the iPhone/Droid or Imo on the iPad and have one site to check for your text messages.  Set up all your accounts, and lot onto all or some of them at any time.

INFORMATION APPS: News, Sports, Reference

Pulse News (iPhone, iPad, Droid) (free)
Zine (iPad only) (free)
Pulse is a great app that aggregates news based on the preferences you put in, and then gives you news feeds that fit your preferences. If you use Google Reader, for example, it pulls in all your RSS feeds. If you don’t understand that last sentence, don’t worry – the basic idea is that it customizes a news feed. If you do nothing else other than set up a real estate news feed on Pulse to keep up with the news, it’s a great use of the app. And looks amazing on iPad.

NYTimes (iPhone, iPad, Droid) (free for now)
A great app for checking out top stories, even if you’re not a subscriber.  You get it free if you’re a subscriber, but soon they’ll be charging heavier users. It’s not clear what the apps will cost, but it will probably allow for some access to top news with payment if you want deeper coverage.

Sportacular (iPhone, iPad, Droid) (free)
For sports updates, Sportacular is quicker than any of the ESPN apps, which are slow and laden with a difficult interface.  Sportacular just gives you the scores by sport, easy to look up.

Wikipanion (iPhone, iPad) (free)
Wikidroid (Droid) (free)
A great app for looking stuff up without having to go to Google.  Wikipedia is a user-generated encyclopedia that is surprisingly effective, and I find myself looking something up on it once or twice a week and always being entertained and informed. Wikipanion and Wikidroid are great apps for getting into Wikipedia in a customized setting without going through the browser.

The Weather Channel (iPhone, iPad, Droid) (free)
The iPhone and iPad come with a very cute weather app, but it doesn’t give you a lot of information.  The Weather Channel app isn’t ideal, but it provides a lot of information for your area with cool graphics.

Google Earth (iPhone, iPad, Droid) (free)
I already mentioned the Google app, but the Google Earth app is so good that I want to highlight it separately.  Google Earth on the computer has been around a while, but the experience on the mobile device is just great because of the location search and just the visual of watching the globe zero down on where you.  A must for real estate people that need to know their terrain and maps.

Maps (iPhone, iPad) (installed)
All smartphones come with the Maps app, but it’s worth pointing out just how great it is and how you need to become familiar with how to set your location and get driving (or walking!) directions.  The idea that years ago you bought a specialized device for this service, and now the your phone has it, is just amazing.

LEISURE APPS: Books, Movies, Food

Yelp (iPhone, iPad, Droid) (free)
Yelp is a great business directory website with user-generated reviews, mostly of restaurants but growing.  This is the kind of website that is geared for mobile device, because you can literally be standing on a corner, go on Yelp to look for nearby restaurants, and choose them based on cuisine and user reviews.  Vastly superior to the Zagat app. I use it all the time, and constantly when traveling.

OpenTable (iPhone, iPad, Droid) (free)
My wife swears by this app, which allows you to find restaurants and then make restaurant reservations right from the app.  No phone calls, no waiting on hold, and you can find the right time by yourself.  Has location-based searching, so you can look for restaurants near where you are.

Kindle App (iPhone, iPad, Droid) (free)
If you have a Kindle, this is a must – all your Kindle books can be loaded onto your Smartphone.  You’d think it would be difficult to read on the phone, but once you get used to reading your email, news, and other items on it, books are not much of a reach. And with the iPhone 4, the resolution is so clear that you don’t get eyestrain. The books also look amazing on an iPad.  Tip: you can store your Kindle books on up to six devices (your Kindle, your iPhone, iPad, etc.), which means that you can get just one Kindle account and share your books on multiple devices with other members of your family (i.e., you get a Kindle and an iPhone, your spouse has an iPhone and an iPad, and your kid has a Droid, all sharing the same book account).

Epicurious (iPhone, iPad, Droid) (free)
The best recipe app, with tons of recipes searchable in a lot of ways.  It also lets you create a shopping list, a great use for your mobile device.

Movie Apps: Fandango and “Movies by Flixster” (iPhone, iPad, Droid) (free)
If you like movies, you need these two apps.  Fandango is the app for the website that allows you to buy tickets online for movies, and Flixster has content from the Rotten Tomatoes movie-reviewing site.

ENTERTAINMENT APPS: Music, Video, TV, Radio
Pocket Tunes (iPhone, iPad) ($6.99)
A great app for people that like to listen to the radio.  Virtually every radio station you can think of in very good audio.  Great for getting local news and sports stations on your iPhone, superior to traditional radios because you don’t get static.

SiriusXM Premium (iPhone, iPad, Droid) (free app with subscription)
If you have either Sirius or XM in your car, you can get access to the satellite radio service on your iPhone or iPad and listen anywhere.  Audio is slow, though, if you’re not connected to a wireless network.

MLB.com At Bat 11 (iPhone, iPad, Droid) ($14.99, lite version for free)
If you are a baseball fan, this app is amazing. You can get updates on any game, with highlight videos that look great, and in many cases can actually watch an out-of-market game right on your device.  Fantastic if you’re a fan of a non-New York team and want to watch the games, and better than getting the cable service that provides access to games because it’s more portable on your device and less annoying to the non-baseball fans around you. If the $15 is too pricey, the free version has some great features also.

Slingplayer Mobile (iPhone, iPad, Droid) ($29 plus Slingplayer)
Slingplayer is a device that costs about $200 which connects to your television and lets you watch THAT television from any internet-connected computer.  This app lets you do it from your Smartphone or iPad, great for traveling if you want to watch something on your DVR. A little pricey, but it allows you, as I have discovered, to watch TV in bed with the headphones on and your spouse happily sleeping.

Shazam (iPhone, iPad, Droid) (free, or $5)
Soundhound (iPhone, iPad, Droid) (free, or $5)
The classic apps for people that like music.  Hear a song you like, just hold your device up and it will identify the song for you so you can buy it. Both are free for a limited number of songs per month, and a few bucks to get unlimited use. They also have other features I haven’t tried (like lyrics)

Pandora (iPhone, iPad, Droid) (free)
Last.FM (iPhone, Droid ) (free)
Slacker Radio (iPhone, Droid) (free)
Pandora was the first breakthrough app on the iPhone, the idea that you could create your own personalized radio station based on very specific music or artists you like, and have the station play similar music.  For example, you can tell the app what artists you like (e.g. “Jack Johnson”), and it will create a virtual radio station for you – not just of that artist, but artists with similar styles.  And if you don’t like a song, you can “skip” it or give it a “thumbs down” and the system will learn your taste. Great for finding new artists that fit your taste.  Pandora has started running commercials, so a number of competitors have gained popularity.  They all have positives and negatives, but having one of them is a must (or all of them, then decide if you want to upgrade one of them).