Never leave the house without your smartphone? New research is trying to ensure that will take care of your keys, too.A house key app under development for smartphones lets users wave their phones at doors to unlock them. The app, called ShareKey, also will allow its owners to electronically share keys with a houseguest, a plumber scheduled to come in for a fix, or anyone else they like -- and to attach certain limits to that access. A company could use the system to control employee and guest access to a building from anywhere in the world. ShareKey offers two new functions: Users can issue digital keys remotely and assign these keys certain user permissions. For instance, you can grant the building superintendent access to my apartment for a short period so that he can open the door for the gas meter to be read while I'm at work."ShareKey users also could limit access to a certain number of times or to certain dates, such as holidays and weekends.
