Mechanical and electronic access control systems inevitably rely on the presence of a physical "key," be it an actual metal key, password entered into a code panel, proximity card, or a magnetic access control card. Typically, these access control methods are not easily changed on the fly – a physical lock would have to be changed and new keys provided to all authorized users, and cards would have to be reprogrammed and reissued from a security office. In addition, losing or misplacing keys and cards is commonplace, creating security headaches.

NFC-capable smartphones can change the equation significantly. While you can never avoid the problem of lost or stolen smartphones, the ability to issue security keys on the fly, and modify or revoke access remotely, presents a number of interesting solutions toward current challenges. This is especially true if the credentialing applications work on any properly equipped smartphone, whatever its operating system.

SecurityInfoWatch recently went over several use cases that make for some compelling reasons for the technology to grow. For example, allowing delivery drivers access to small, secure rooms for after-hours delivery, and then immediately revoking access when they leave. Another example would be rental properties where door locks and door lock codes would not have to be changed after the guests leave and accidentally take the keys with them. For this, the smartphone app would simply revoke access at the time of their scheduled or actual departure.

Research firm IHS estimates that the overall market for cloud-based access control services will increase to about $530 million by 2018 and then more than triple that by 2025. This acceleration, however, is dependent on compatible hardware being installed at access-controlled locations, something the company sees as a growth area as products come down in price. It is very likely that China-based manufacturers of such equipment will have an essential role in lowering prices of such equipment to the point that wide adoption becomes feasible.