It's weird to think that we're living in 2020 and still using the same technology to unlock doors as people thousands of years ago.

Slowly, however, house keys are starting to catch up to the times.

Smartphones, key fobs and PIN pads are becoming increasingly common ways to open your front door - even when you're not standing in front of it. "Whether that makes sense for everyone is doubtful," says Juergen Spermann from the Federal Association of Security Technology in Germany. "Electronic lock systems may be more convenient, but as far as security goes, they're not absolutely necessary," he says.

But think of the situations where opening and closing your house door online would be practical - "You could, for example, give those key rights to a visitor," says Stephan Schmidt, managing director of a lock industry association in Germany. The guest could receive a code online that allows them to enter a place at a certain time. "When the visitor shuts the door again, the code then expires," adds Schmidt.

Electronic lock systems that aren't connected to the Internet but are remote-controlled are already becoming widespread. Some examples include doors that require a PIN code to enter, or a transponder key.

Most people, however, still have a house key with a mechanical lock system. But that's not to say that these locks are old-fashioned, says Schmidt. "Mechanical locking cylinders have been around for many decades. But they are constantly being improved and supplemented with cross locks and locking pins." Customers can now find technically sophisticated locks with fine, high-quality mechanics, say experts.

"The locking cylinder on its own doesn't make a door secure," says Spermann. "To withstand any access attempts by intruders, it must be as massive as possible, as well as be outfitted with multiple fittings and door bars," according to the German security expert.

Making your door as secure as possible doesn't always have to mean buying a new door - old doors, depending on their condition, can be upgraded as well. It's just important to ensure that the door's elements - leaf, hinges, frame and locks - and its security additions are sensibly coordinated and are professionally installed.

 - dpa