Openways has developen an application that allows you to open your hotel room with your smartphone. It will be compatible with most hotel lock technologies. For those that have ever had problems getting your key card to work, this is great news. This technology has the potential to go beyond locked hotel doors into other applications.
According to Openways the app uses the speaker in your smartphone to generate a specific tone that is picked up by the lock mechanism. This tone is different at each use, so there is no danger of someone recording the tone to get access.