The Internet of Things (IoT) is rapidly transitioning from a technology of the future to a must-have business tool for the here and now. Before the end of this year, IoT devices will outnumber mobile devices, and Gartner projects more than 21 billion IoT devices will be connected to the internet by 2020.

The commercial opportunities IoT provides are enormous, and they're as accessible to small and midsize businesses (SMBs) as they are to large enterprises. Gartner's 2017 IoT Survey found that the most significant internal benefits include increased worker productivity, remote monitoring and control of operations, and improved businesses processes. IoT is also enabling new business models and revenue streams, such as additional value-added services after the sale of a product and increased upselling of premium products and services.

Here are five IoT applications you can start using to improve your business performance right now:

1. Smart locks

Smart locks can be used to increase both convenience and security. For example, retailers can operate them remotely from a central in-store location to give customers access to restricted areas of a store, an application Robb Hecht, an adjunct professor of marketing at Baruch College, says is growing in popularity. Property managers can use them to allow service workers and delivery people to enter a building without having to be there in person to unlock the door. "SMB owners can stay focused on building their businesses rather than having to drive across town," he says.

Smart locks improve security because digital keys are less vulnerable to theft and loss than physical keys are. Smart locks enable SMB owners to create and revoke keys for employees and other users at any time. This can be a boon to SMBs with high employee turnover rates. Most smart-lock apps also create detailed logs of who unlocked them and when, providing an easy way for owners to make sure employees are opening and closing at the right times.

2. Smart lighting and HVAC

Smart thermostats are already an IoT fixture in the consumer market, but SMBs stand to reap more significant benefits from commercial applications of smart lighting and HVAC (heating/ventilation/air-conditioning) products and controls. Smarting lighting provides an immediate and quantifiable ROI for SMBs in the form of documented energy savings. IoT-connected controls coupled with LED lighting systems can result in energy savings of up to 90 percent.

Likewise, IoT-enabled HVAC systems can return significant energy cost savings. Using sensors to determine when rooms are empty or occupied, they can adjust heating and cooling settings appropriately. Some systems use machine learning (ML) to become smarter over time, leading to even greater savings. "The cost savings of environmental IoT controls in industry have been well-documented," says Werner Krebs, CEO of Acculation, a data science consulting firm.

3. Voice assistant

How great would it be if you could hire an extremely efficient assistant who never complained, called in sick, or asked for a raise? You've probably got one already, enabled by IoT over your smart phone, computer, or smart speaker.

"It's widely believed that voice assistants will be an integral part of business operations over the next five years," says Charlotte Brown, CEO of Adelie Ventures, a business strategy firm. "SMBs can take advantage of Google Assistant and other voice assistant IoT technologies (such as Amazon's Alexa and Apple's Siri) right now by linking them to task management systems, notes, and calendars."

Voice assistants can also control most other smart IoT devices, freeing up time for SMB owners to focus on more-strategic business issues. Brown believes the efficiency gains and accuracy that voice assistants provide make them one of the best IoT applications available to SMBs right now.

4. Supply Chain Data Loggers

This is one area where IoT presents vast opportunities for businesses of all sizes, Krebs says. For example, IoT logistics applications make it possible to tag fragile or temperature-sensitive products such as eggs, milk, or flowers and continuously monitor their temperature, the temperature and humidity of their storage areas, and shock and vibration levels during shipment.

"This reduces supply chain costs by allowing the shipper to prove the goods were maintained at the correct temperatures during shipping," Krebs says. "And it reduces buyer costs since they can eliminate improperly maintained shipments or spoiled goods from their supplies before they even arrive at their destination."

IoT-enabled, data-logging sensors can also be used to track deliveries from vendors to manufacturing facilities, to track movement of materials and finished products for assembly or shipping inside facilities, and to accurately track vehicles for more efficient fleet management.

5. Barcode readers & RFID tags

Large retail enterprises have been using barcode readers and RFID (radio frequency identification) scanners for many years, most often as integral parts of expensive point-of-sale systems. The devices enable data collection that can be used for many purposes, including inventory tracking and updating, merchandise reordering, and loss prevention by tracking location of merchandise within the store.

Thanks to IoT, now there are many affordable options that provide the same benefits to small retailers and other SMBs, either as standalone devices or in combination with a smart phone or tablet, says Adam Sbeta, cyber security analyst and senior team lead at Oakland Managed IT & Cyber Security Services. "The goal of all these devices is to collect data, and it's a simple matter for any savvy technician to integrate that data into your invoicing or inventory system,' he says.

Take advantage of IoT, but proceed with caution

This is just a small sampling of all that IoT has to offer SMBs right now, and more new applications are being introduced all the time. Take the time to see what different IoT apps have to offer, and make sure the benefits align with your business objectives and goals. Most importantly, don't forget about security, Sbeta emphasizes.

"Make sure you always change the default passwords for any IoT devices you deploy, and don't use the same password for everything," he emphasizes. "Hackers already have many repositories of stolen and breached passwords on the Dark Web. The last thing you want is someone taking over your smart lock or other IoT device."