Advanced Task Killer: This is the app I use most on my Desire HD. With this app you can kill all the tasks opened on your phone with just a click. This app shortcut is well deserved to be on my home screen. By killing all the running tasks you can free the phone's memory, hence speeding up your phone and saving battery life.
Air Control Lite: This is a fun and addictive game. All you need to do is become a pilot and land the airplanes, helicopters on their runways and helipads respectively without collisions.
Angry Birds Seasons: Angry Birds is the top free game for both Android and iOS. Seasons is the new version of angry birds with many seasons like Hogs and Kisses, Seasons Greedings, Trick or Treat etc.
Barcode Scanner: This is yet another app I use most on my HTC Desire HD to scan the QR codes while downloading apps for my phone. With this app you can scan barcodes on products then look up prices and reviews, scan Data Matrix and QR Codes containing URLs, contact info, etc.
Blogaway: This is the must have app for Bloggers on Desire HD. Though Blogger released the official app, this app has some unique features like editing and viewing older posts etc. Hence it can replace the official blogger app on your phone.
CamCard Lite: This app is used extract the scanned the business cards using Desire HD's camera and save all the info like name, phone number, fax etc into contacts. Also it will automatically trim and enhance card image before saving it into contacts.
CamScanner: This app turns our HTC Desire HD into a document scanner machine. This app helps you to scan and manage your documents, whiteboard discussions and receipts easily. Also the smart image cropping and enhancement algorithm ensures that the scanned images are clear and recognizable.
Documents To Go: With this app you can turn your phone into a mobile office. You can view Microsoft Word, Excel and PowerPoint files. Though the free version is available for basic needs like viewing, it doesn't allow you to edit documents. You need to purchase full version to edit documents on a go.
Epicurious: This is the number one cooking app for both Android and iOS. The app has 28,000 delicious dishes along with shopping list support. You can simply view the recipe, add the required ingredients to shopping list and plan for your cooking accordingly.
FxCamera: This app will allow you to capture pictures of your friends in a funny way with various effects like ToyCam, Polandroid, Fisheye, SymmetriCam, Warhol, Normal etc.
Google Sky Map: This app turns your HTC Desire HD into a window on the night sky. All you need to do is just point your phone at the sky, and the app will show you the stars, planets, constellation etc that is there on the sky using your phone's GPS. You can also browse the skies in manual mode.
Handcent SMS: This is the best app for messaging on your android powered desire HD phone. I replaced the default messaging froyo app with this one on my phone. The app has great features like Group sending options, SMS Popup with quick text, iPhone look messaging system, photo and emoji icons support etc.
iBasket: I used to play this game on my friend's iPhone and now I am playing it on my Desire HD. Its a fun playing and addictive game. You can also challenge your friends right from your phone.
Instant Heart Rate: This app turns your phone into a heart rate monitor. The app uses the phone camera to calculate heart rate. Just place your finger gently over the camera for 10 seconds and your current heart rate will be displayed on your Desire HD. It was accurate and also tested by professional doctors.
Layar: This is an Augmented Reality app I use on my desire HD. Layar app uses camera, 3G and phone's GPS to display digital information lapped onto the phone's view.
MapDroyd: I was using Google Maps before I found this app on the market. Google Maps requries 3G connectivity always while using it. But MapDroyd app provides offline maps solution to the Desire HD. It offers world-wide off-line maps powered by OpenStreetMap. Though it is not as good as Google Maps, considering data connectivity charges its a great alternative to it.
MyFitnessPal: This is a calorie counter and diet tracker application. In-fact this app has the largest database of food and with its amazing features, this will help you in keeping your diet everyday.
NinJump: I loved this game playing on iPhone and now on my desire HD. This is a fun and addictive game. All you have to do is rise to the top by avoiding obstacles and become a ninja master.
Paper Toss: This game is from same makers of NinJump. I think the makers, BackFlip studios know how to engage people by making fun and addictive games. In this game you need to toss a paper into dustbin. It has various levels of difficulites and various places like airport, basement, restroom etc.
Photoshop Express: With this app you can edit and share photos on a go. There are many editing options like crop, rotate, adjust color, artistic effects etc. This is a must have app on your desire HD if you are a photo-phobic.
Raging Thunder 2: If you love racing games, then this game is for you. It is an adrenaline pumping 3D racer. It also features cross-platform multiplayer gaming support.
Schedalls: This is a very much useful app to send messages to friends at right time. Suppose you want to wish your friend on his/her birthday at exactly 11:59 PM, this app helps you to schedule the messages and the message will be sent to them in the exact time. No worryings about forgetting to send an important message.
SpeedTest: This app is used to determine the speed of your 3G connectivity. Its an official app from popular site speedtest.net.
SuperBox: This app has 10 tools in total like Memory monitor, app2sd, cache cleaner, task killer, battery widget etc.
TeamViewer: This is a remote desktop application. With this app, I can access my home desktop from my HTC Desire HD while on a go.
To Do List: This is a free and simple to do list app for Desire HD. With this app you can add, edit or delete tasks, write notes, set alerts and even make calls.
Winamp: The old winamp desktop app is back for android phones. With this app you can play, manage and sync music from your desktop to your Desire HD.
WorldWars: This is a fun and addictive game for your Desire HD. I finished the game with difficulty 1 at 2nd attempt but when I increase the difficulty level, the game is really hard to play and we have to think our own strategies to defend against stronger side.