As someone who attends a lot of trade shows each year, I have found that my smartphone is an invaluable tool for helping me to function efficiently while on site. Here are five of my favorite smartphone apps to use while attending a trade show.

Note: This article is also available as an image gallery and a video hosted by TechRepublic columnist Tom Merritt.

1: CamCard

One of the great things about attending trade shows is that if you play your cards right, you can make a lot of contacts. Of course the flip side to that is that you might be inundated with business cards, which can all start looking alike after a while. Not only that, Murphy’s Law specifically states that the only business card you will misplace is the one that you needed the most.

CamCard (Figure A) is a free app that allows you to take pictures of business cards and save the contents to your phone. Upon photographing a card, CamCard uses optical character recognition to recognize the card data, but you can edit the data if necessary. CamCard also enables you to add custom fields and to add reference notes to the card information.

Figure A

CamCard is available for Windows Phone, iOS, and Android.

2: Track My Budget

It isn’t exactly a secret that attending trade shows can be expensive. Whether you are on an expense account or you’re footing the bill yourself, there is probably a budget you need to stick to.

Track My Budget (Figure B) will help you to keep track of spending as it relates to your budget. Although the app is geared toward household budgets, it works surprisingly well for keeping track of spending while on the road. It allows you to set up custom categories, such as flights and hotels, and then categorize your transactions. You can enter your total travel budget as Income and the app will show you how much you have spent and how much money remains in your budget. Best of all, the app allows you to enter certain expenses (such as parking at the airport or your morning coffee) as recurring so that you don’t have to enter the expense manually each day.

Figure B

Track My Budget is available for Android and Windows Phone. There is also an iOS version that is designed to link to your Google calendar.

3: Sticky Notes

When I meet people at a trade show, there often isn’t enough time to speak with them at length about doing business. The trade show environment is great for introductions, but follow-ups are almost always required. Of course, without a little bit of help it can be tough to remember who you were supposed to follow up with and why.

Sticky Notes (Figure C) is a free app that lets you create a collection of virtual sticky notes. You can choose the color and font for each note, and there is even an option to dictate the note. Best of all, you can generate reminders for sticky notes and the Windows Phone version lets you pin a note to the Start screen.

Figure C

Sticky Notes is available for iOS, Android, and Windows Phone.

4: Dude, Where’s My Car

One of my most indispensable tools when I go to a trade show is an app to keep track of where I parked. Let’s face it. If I’m gone for a week, it can be tough to remember where I parked my car at the airport. Furthermore, I usually rent a car when I get where I am going. Long days at the conference can blur together and it is sometimes tough to remember if I parked in Level 4 Section D today or if that was where I parked yesterday.

Dude, Where’s My Car (Figure D) is a free app that helps you keep track of where you parked. It’s simple, but effective. It allows you to create a named location for where you parked. When it is time to locate your car, the app uses mapping to show you how to get back to it. On my phone, the mapping software defaults to walking mode, but since I am in Houston at the moment and my car is in Charlotte, I have the option of getting driving directions to my car.

Figure D

Dude, Where’s My Car is available for iOS, Android, and Windows Phone.

5: Expensify

It never ceases to amaze me just how many receipts I can accumulate within a short amount of time when attending a conference. Those receipts are important for me to keep track of because some are tax deductible and others may be reimbursable.

Expensify (Figure E) is a free app for keeping track of those receipts. It lets you photograph your receipts and then uses optical character recognition to extract data from them. You also have the option of entering data manually. Once the data has been entered, you can compile a collection of receipts into an expense report.

Figure E

Expensify is available for iOS, Android, and Windows Phone.